# 13.6. Iterator Map

• Map (convert) elements in sequence

• Generator (lazy evaluated)

• map(callable, *iterables)

• required callable - Function

• required iterables - 1 or many sequence or iterator objects

>>> from inspect import isgeneratorfunction, isgenerator
>>>
>>>
>>> isgeneratorfunction(map)
False
>>>
>>> result = map(float, [1,2,3])
>>> isgenerator(result)
False


## 13.6.1. Example

>>> result = (float(x) for x in range(0,5))
>>>
>>> list(result)
[0.0, 1.0, 2.0, 3.0, 4.0]

>>> result = map(float, range(0,5))
>>>
>>> list(result)
[0.0, 1.0, 2.0, 3.0, 4.0]


## 13.6.2. Problem

>>> data = [1, 2, 3]
>>> result = []
>>>
>>> for x in data:
...     result.append(float(x))
>>>
>>> print(result)
[1.0, 2.0, 3.0]


## 13.6.3. Solution

>>> data = [1, 2, 3]
>>> result = map(float, data)
>>>
>>> list(result)
[1.0, 2.0, 3.0]


## 13.6.4. Lazy Evaluation

>>> data = [1, 2, 3]
>>> result = map(float, data)
>>>
>>> next(result)
1.0
>>> next(result)
2.0
>>> next(result)
3.0
>>> next(result)
Traceback (most recent call last):
StopIteration


## 13.6.5. Multi Parameters

>>> def myfunc(x):
...     return sum(x)
>>>
>>>
>>> DATA = [
...     (1,2),
...     (3,4),
... ]
>>>
>>> result = map(myfunc, DATA)
>>> print(list(result))
[3, 7]


## 13.6.6. Starmap

>>> from itertools import starmap
>>>
>>>
>>> DATA = [
...     (3.1415, 3),
...     (2.71828, 2),
... ]
>>>
>>> result = starmap(round, DATA)  # round(number=3.1415, ndigits=2)
>>> print(list(result))
[3.142, 2.72]


## 13.6.7. Partial

>>> from functools import partial
>>>
>>>
>>> round1 = partial(round, ndigits=1)
>>> DATA = [1.111, 2.222, 3.333]
>>>
>>> result = map(round1, DATA)  # round(number=1.111, ndigits=1)
>>> print(list(result))
[1.1, 2.2, 3.3]


## 13.6.8. More Args

>>> numbers = [1.1111, 2.2222, 3.3333]
>>> prec = [1, 2, 3]
>>>
>>> result = map(round, numbers, prec)
>>> list(result)
[1.1, 2.22, 3.333]

• round(1.1111, prec=1)

• round(2.2222, prec=2)

• round(3.3333, prec=3)

>>> numbers = [1.1111, 2.2222, 3.3333]
>>> prec = [1, 2, 3, 4]
>>>
>>> result = map(round, numbers, prec)
>>> list(result)
[1.1, 2.22, 3.333]

>>> numbers = [1.1111, 2.2222, 3.3333, 4.444]
>>> prec = [1, 2, 3]
>>>
>>> result = map(round, numbers, prec)
>>> list(result)
[1.1, 2.22, 3.333]


## 13.6.9. Performance

>>> def even(x):
...     return x % 2 == 0

>>>
... %%timeit -r 1000 -n 1000
... result = [float(x) for x in data if even(x)]
1.9 µs ± 206 ns per loop (mean ± std. dev. of 1000 runs, 1,000 loops each)

>>>
... %%timeit -r 1000 -n 1000
... result = list(map(float, filter(parzysta, data)))
1.66 µs ± 175 ns per loop (mean ± std. dev. of 1000 runs, 1,000 loops each)


## 13.6.10. Use Case - 0x01

Built-in functions:

>>> DATA = [1, 2, 3]
>>> result = map(float, DATA)
>>>
>>> tuple(map(float, DATA))
(1.0, 2.0, 3.0)

>>> DATA = [1, 2, 3]
>>> result = map(float, DATA)
>>>
>>> set(map(float, DATA))
{1.0, 2.0, 3.0}

>>> DATA = [1, 2, 3]
>>> result = (float(x) for x in DATA)
>>>
>>> list(result)
[1.0, 2.0, 3.0]

>>> DATA = [1.1, 2.2, 3.3]
>>> result = map(round, DATA)
>>>
>>> list(result)
[1, 2, 3]


## 13.6.11. Use Case - 0x02

>>> def square(x):
...     return x ** 2
>>>
>>>
>>> DATA = [1, 2, 3]
>>> result = map(square, DATA)
>>>
>>> list(result)
[1, 4, 9]


## 13.6.12. Use Case - 0x03

>>> def increment(x):
...     return x + 1
>>>
>>>
>>> DATA = [1, 2, 3, 4]
>>> result = map(increment, DATA)
>>>
>>> list(result)
[2, 3, 4, 5]


## 13.6.13. Use Case - 0x04

>>> def translate(letter):
...     return PL.get(letter, letter)
>>>
>>>
>>> DATA = 'zażółć gęślą jaźń'
>>> PL = {'ą': 'a', 'ć': 'c', 'ę': 'e',
...       'ł': 'l', 'ń': 'n', 'ó': 'o',
...       'ś': 's', 'ż': 'z', 'ź': 'z'}
>>>
>>> result = map(translate, DATA)
>>> ''.join(result)
'zazolc gesla jazn'


## 13.6.14. Use Case - 0x05

Standard input:

>>> import sys
>>>
>>>
... print(sum(map(int, sys.stdin)))

\$ cat ~/.profile |grep addnum
alias addnum='python -c"import sys; print(sum(map(int, sys.stdin)))"'


## 13.6.15. Use Case - 0x06

>>> import requests
>>>
>>> url = 'https://python3.info/_static/iris-dirty.csv'
>>>
>>> data = requests.get(url).text
>>> nrows, nfeatures, *class_labels = header.strip().split(',')
>>> label_encoder = dict(enumerate(class_labels))

>>> result = []
>>> for row in rows:
...     *features, species = row.strip().split(',')
...     features = map(float, features)
...     species = label_encoder[int(species)]
...     row = tuple(features) + (species,)
...     result.append(row)

>>> def decode(row):
...     *features, species = row.strip().split(',')
...     features = map(float, features)
...     species = label_encoder[int(species)]
...     return tuple(features) + (species,)
>>>
>>> result = map(decode, rows)

>>> def decode(row):
...     *features, species = row.strip().split(',')
...     features = map(float, features)
...     species = label_encoder[int(species)]
...     return tuple(features) + (species,)
>>>
>>> with open('/tmp/myfile.csv') as file:
...     for line in map(decode, file):
...         print(line)


## 13.6.16. Use Case - 0x07

SetUp:

>>> from doctest import testmod as run_tests


Data [1]:

>>> DATA = """150,4,setosa,versicolor,virginica
... 5.1,3.5,1.4,0.2,0
... 7.0,3.2,4.7,1.4,1
... 6.3,3.3,6.0,2.5,2
... 4.9,3.0,1.4,0.2,0
... 6.4,3.2,4.5,1.5,1
... 5.8,2.7,5.1,1.9,2"""


Definition:

>>> def get_labelencoder(header: str) -> dict[int, str]:
...     """
...     >>> get_labelencoder('150,4,setosa,versicolor,virginica')
...     {0: 'setosa', 1: 'versicolor', 2: 'virginica'}
...     """
...     nrows, nfeatures, *class_labels = header.split(',')
...     return dict(enumerate(class_labels))
>>>
>>> run_tests()
TestResults(failed=0, attempted=1)

>>> def get_data(line: str) -> tuple:
...     """
...     >>> convert('5.1,3.5,1.4,0.2,0')
...     (5.1, 3.5, 1.4, 0.2, 'setosa')
...     >>> convert('7.0,3.2,4.7,1.4,1')
...     (7.0, 3.2, 4.7, 1.4, 'versicolor')
...     >>> convert('6.3,3.3,6.0,2.5,2')
...     (6.3, 3.3, 6.0, 2.5, 'virginica')
...     """
...     *values, species = line.split(',')
...     values = map(float, values)
...     species = label_encoder[int(species)]
...     return tuple(values) + (species,)
>>>
>>> run_tests()
TestResults(failed=0, attempted=3)

>>> header, *lines = DATA.splitlines()
>>> result = map(get_data, lines)

>>> list(result)
[(5.1, 3.5, 1.4, 0.2, 'setosa'),
(7.0, 3.2, 4.7, 1.4, 'versicolor'),
(6.3, 3.3, 6.0, 2.5, 'virginica'),
(4.9, 3.0, 1.4, 0.2, 'setosa'),
(6.4, 3.2, 4.5, 1.5, 'versicolor'),
(5.8, 2.7, 5.1, 1.9, 'virginica')]


## 13.6.17. Use Case - 0x08

>>>
... import pandas as pd
...
...
... DATA = 'https://python3.info/_static/phones-pl.csv'
...
... result = (
...     pd
...     .set_index('datetime', drop=True)
...     .drop(columns=['id'])
...     .loc['2000-01-01':'2000-03-01']
...     .query('item == "sms"')
...     .groupby(['period','item'])
...     .agg(
...         duration_count = ('duration', 'count'),
...         duration_sum = ('duration', 'sum'),
...         duration_median = ('duration', 'median'),
...         duration_mean = ('duration', 'mean'),
...         duration_std = ('duration', 'std'),
...         duration_var = ('duration', 'var'),
...         value = ('duration', lambda column: column.mean().astype(int))
...     )
... )


## 13.6.18. Use Case - 0x09

>>> from functools import reduce
>>>
>>>
>>> def even(x):
...     return x % 2 == 0
>>>
>>> def positive(x):
...     return x > 0
>>>
>>> def non_negative(x):
...     return x >= 0
>>>
>>> def square(x):
...     return x ** 2
>>>
...     return x + 1
>>>
>>> def minus1(x):
...     return x + 1

>>> data = range(0, 1024)
>>> data = filter(even, data)
>>> data = filter(positive, data)
>>> data = filter(non_negative, data)
>>> data = map(square, data)
>>> data = map(minus1, data)
>>>
>>> result
178434046

>>> filters = [
...     even,
...     positive,
...     non_negative,
... ]
>>>
>>> maps = [
...     square,
...     minus1,
... ]
>>>
>>> def apply(data, fn):
...     return map(fn, data)
>>>
>>>
>>> data = range(0, 1024)
>>> data = reduce(apply, filters, data)
>>> data = reduce(apply, maps, data)
>>>
>>> result
3072


## 13.6.19. Use Case - 0x0A

>>> from dataclasses import dataclass
>>>
>>>
>>> DATA = """root:x:0:0:root:/root:/bin/bash
... shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
... halt:x:7:0:halt:/sbin:/sbin/halt
... mwatney:x:1000:1000:Mark Watney:/home/mwatney:/bin/bash
... mlewis:x:1001:1001:Melissa Lewis:/home/mlewis:/bin/bash
... rmartinez:x:1002:1002:Rick Martinez:/home/rmartinez:/bin/bash
... avogel:x:1003:1003:Alex Vogel:/home/avogel:/bin/bash
... bjohanssen:x:1004:1004:Beth Johanssen:/home/bjohanssen:/bin/bash
... cbeck:x:1005:1005:Chris Beck:/home/cbeck:/bin/bash"""
>>>
>>>
>>> @dataclass
... class SystemAccount:
...     uid: int
>>>
>>> @dataclass
... class UserAccount:
...     uid: int
>>>
>>>
>>> def account(line):
...     records = line.strip().split(':')
...     uid = int(records[2])
...     if uid < 1000:
...     else:
>>>
>>> def system(account):
...     return account.uid < 1000

>>> all_accounts = map(account, DATA.splitlines())
>>> list(all_accounts)

>>> sys_accounts = filter(system, all_accounts)
>>>
>>> list(sys_accounts)


## 13.6.21. Assignments

"""
* Assignment: Iterator Map Float
* Type: class assignment
* Complexity: easy
* Lines of code: 1 lines
* Time: 2 min

English:
1. Use map() to apply function float() to DATA
2. Define result: map with result
3. Run doctests - all must succeed

Polish:
1. Użyj map() aby zaaplikować funkcję float() do DATA
2. Zdefiniuj result: map z wynikiem
3. Uruchom doctesty - wszystkie muszą się powieść

Hints:
* map()
* float()

Tests:
>>> import sys; sys.tracebacklimit = 0
>>> from inspect import isfunction

>>> assert result is not Ellipsis, \
'Assign result to variable: result'

>>> assert type(result) is map, \
'Variable result has invalid type, should be map'

>>> result = list(result)
>>> assert type(result) is list, \
'Evaluated result has invalid type, should be list'

>>> assert all(type(x) is float for x in result), \
'All rows in result should be float'

>>> result
[1.0, 2.0, 3.0]
"""

DATA = [1, 2, 3]

# Use map() to apply function float() to DATA
# type: map
result = ...


"""
* Assignment: Iterator Map Apply
* Type: class assignment
* Complexity: easy
* Lines of code: 3 lines
* Time: 2 min

English:
1. Define function cube():
a. takes one argument
b. returns its argument cubed (raised to the power of 3)
2. Use map() to apply function cube() to DATA
3. Define result: map with result
4. Run doctests - all must succeed

Polish:
1. Zdefiniuj funckję cube():
a. przyjmuje jeden argument
b. zwraca argument podniesiony do sześcianu (do 3 potęgi)
2. Użyj map() aby zaaplikować funkcję cube() do DATA
3. Zdefiniuj result: map z wynikiem
4. Uruchom doctesty - wszystkie muszą się powieść

Hints:
* map()
* pow()

Tests:
>>> import sys; sys.tracebacklimit = 0
>>> from inspect import isfunction

>>> assert isfunction(cube), \
'Object cube must be a function'
>>> assert result is not Ellipsis, \
'Assign result to variable: result'

>>> assert type(result) is map, \
'Variable result has invalid type, should be map'

>>> result = list(result)
>>> assert type(result) is list, \
'Evaluated result has invalid type, should be list'

>>> assert all(type(x) is int for x in result), \
'All rows in result should be int'

>>> result
[0, 1, 8, 27, 64, 125, 216, 343, 512, 729]
"""

DATA = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

# Returns its argument cubed (raised to the power of 3)
# type: Callable[[int], [int]]
def cube(x):
...

# Cube numbers in DATA
# type: map
result = ...


"""
* Assignment: Iterator Map Apply
* Type: class assignment
* Complexity: easy
* Lines of code: 3 lines
* Time: 3 min

English:
1. Define function upper():
a. takes one argument (str)
b. returns argument uppercased
2. Use map() to apply function upper() to DATA
3. Define result: map with result
4. Run doctests - all must succeed

Polish:
1. Zdefiniuj funckję upper():
a. przyjmuje jeden argument (str)
b. zwraca argument dużymi literami
2. Użyj map() aby zaaplikować funkcję upper() do DATA
3. Zdefiniuj result: map z wynikiem
4. Uruchom doctesty - wszystkie muszą się powieść

Hints:
* map()
* str.upper()

Tests:
>>> import sys; sys.tracebacklimit = 0
>>> from inspect import isfunction

>>> assert isfunction(upper), \
'Object upper must be a function'
>>> assert result is not Ellipsis, \
'Assign result to variable: result'

>>> assert type(result) is map, \
'Variable result has invalid type, should be map'

>>> result = list(result)
>>> assert type(result) is list, \
'Evaluated result has invalid type, should be list'

>>> assert all(type(x) is str for x in result), \
'All rows in result should be str'

>>> result
['A', 'B', 'C']
"""

DATA = ['a', 'b', 'c']

# Define function upper():
# - takes one argument (str)
# - returns argument uppercased
# type: Callable[[str], [str]]
def upper():
...

# Use map() to apply function upper() to DATA
# type: map
result = ...


"""
* Assignment: Iterator Map Apply
* Type: class assignment
* Complexity: easy
* Lines of code: 1 lines
* Time: 2 min

English:
1. Use map() to apply function str.upper() to DATA
2. Do not define own function
3. Define result: map with result
4. Run doctests - all must succeed

Polish:
1. Użyj map() aby zaaplikować funkcję str.upper() do DATA
2. Nie definiuj własnej funkcji
3. Zdefiniuj result: map z wynikiem
4. Uruchom doctesty - wszystkie muszą się powieść

Hints:
* map()
* str.upper()

Tests:
>>> import sys; sys.tracebacklimit = 0
>>> from inspect import isfunction

>>> assert result is not Ellipsis, \
'Assign result to variable: result'

>>> assert type(result) is map, \
'Variable result has invalid type, should be map'

>>> result = list(result)
>>> assert type(result) is list, \
'Evaluated result has invalid type, should be list'

>>> assert all(type(x) is str for x in result), \
'All rows in result should be str'

>>> result
['A', 'B', 'C']
"""

DATA = ['a', 'b', 'c']

# Use map() to apply function str.upper() to DATA
# type: map
result = ...


"""
* Assignment: Iterator Map FromISOFormat
* Complexity: easy
* Lines of code: 1 lines
* Time: 2 min

English:
1. Define result: map with parsed DATA dates
2. Use map() and datetime.fromisoformat()
3. Run doctests - all must succeed

Polish:
1. Zdefiniuj result: map ze sparsowanymi datami DATA
2. Użyj map() oraz datetime.fromisoformat()
3. Uruchom doctesty - wszystkie muszą się powieść

Hints:
* map()
* datetime.fromisoformat()

Tests:
>>> import sys; sys.tracebacklimit = 0
>>> from pprint import pprint

>>> assert result is not Ellipsis, \
'Assign result to variable: result'

>>> assert type(result) is map, \
'Variable result has invalid type, must be a map'

>>> result = list(result)
>>> assert type(result) is list, \
'Variable result has invalid type, must be a list'

>>> assert all(type(element) is datetime for element in result), \
'All elements in result must be a datetime'

>>> pprint(result, width=30)
[datetime.datetime(1961, 4, 12, 6, 7),
datetime.datetime(1961, 4, 12, 6, 7)]
"""

from datetime import datetime

DATA = [
'1961-04-12 06:07',
'1961-04-12 06:07:00',
]

# Define result: map with parsed DATA dates
# type: map
result = ...


"""
* Complexity: medium
* Lines of code: 1 lines
* Time: 2 min

English:
1. Define result: map with logged users from DATA
2. Run doctests - all must succeed

Polish:
1. Zdefiniuj result: map z zalogowanymi użytkownikami z DATA
2. Uruchom doctesty - wszystkie muszą się powieść

Hints:
* map()
* class.method(instance)

Tests:
>>> import sys; sys.tracebacklimit = 0
>>> from pprint import pprint

>>> assert result is not Ellipsis, \
'Assign result to variable: result'

>>> assert type(result) is map, \
'Variable result has invalid type, should be map'

>>> result = list(result)
>>> assert type(result) is list, \
'Variable result has invalid type, must be a list'

>>> assert all(type(element) is str for element in result), \
'All elements in result must be a str'

>>> pprint(result, width=30)
"""

class User:

USERS = [
User('mwatney', 'Ares3'),
User('mlewis', 'Nasa69'),
]

result = ...


"""
* Assignment: Iterator Map Logs
* Complexity: medium
* Lines of code: 7 lines
* Time: 8 min

English:
1. Define parse() to extract date, time, level and message
2. Define result: map with parse() function applied to DATA
3. Run doctests - all must succeed

Polish:
1. Zdefiniuj parse() do wyciągnięcia dat, czasu, poziomu i wiadomości
2. Zdefiniuj result: map z funkcją parse() zaaplikowaną do danych
3. Uruchom doctesty - wszystkie muszą się powieść

Hint:
* Note, that last time has no seconds
* This is not bug, time without seconds is in NASA history records [1]

References:
[1] National Aeronautics and Space Administration.
Apollo 11 timeline.
Year: 1969. Retrieved: 2021-03-25.
URL: https://history.nasa.gov/SP-4029/Apollo_11i_Timeline.htm

Hints:
* str.splitlines()
* str.split(', ', maxsplit=3)
* date.fromisoformat()
* time.fromisoformat()
* datetime.combine()

Tests:
>>> import sys; sys.tracebacklimit = 0
>>> from pprint import pprint

>>> assert result is not Ellipsis, \
'Assign result to variable: result'

>>> assert type(result) is map, \
'Variable result has invalid type, should be map'

>>> result = list(result)
>>> assert type(result) is list, \
'Variable result has invalid type, must be a list'

>>> assert all(type(row) is dict for row in result), \
'All elements in result must be dict'

>>> pprint(result)
[{'datetime': datetime.datetime(1969, 7, 14, 21, 0),
'level': 'INFO',
'message': 'Terminal countdown started'},
{'datetime': datetime.datetime(1969, 7, 16, 13, 31, 53),
'level': 'WARNING',
'message': 'S-IC engine ignition (#5)'},
{'datetime': datetime.datetime(1969, 7, 16, 13, 33, 23),
'level': 'DEBUG',
'message': 'Maximum dynamic pressure (735.17 lb/ft^2)'},
{'datetime': datetime.datetime(1969, 7, 16, 13, 34, 44),
'level': 'WARNING',
'message': 'S-II ignition'},
{'datetime': datetime.datetime(1969, 7, 16, 13, 35, 17),
'level': 'DEBUG',
'message': 'Launch escape tower jettisoned'},
{'datetime': datetime.datetime(1969, 7, 16, 13, 39, 40),
'level': 'DEBUG',
'message': 'S-II center engine cutoff'},
{'datetime': datetime.datetime(1969, 7, 16, 16, 22, 13),
'level': 'INFO',
'message': 'Translunar injection'},
{'datetime': datetime.datetime(1969, 7, 16, 16, 56, 3),
'level': 'INFO',
'message': 'CSM docked with LM/S-IVB'},
{'datetime': datetime.datetime(1969, 7, 16, 17, 21, 50),
'level': 'INFO',
'message': 'Lunar orbit insertion ignition'},
{'datetime': datetime.datetime(1969, 7, 16, 21, 43, 36),
'level': 'INFO',
'message': 'Lunar orbit circularization ignition'},
{'datetime': datetime.datetime(1969, 7, 20, 17, 44),
'level': 'INFO',
'message': 'CSM/LM undocked'},
{'datetime': datetime.datetime(1969, 7, 20, 20, 5, 5),
'level': 'WARNING',
'message': 'LM powered descent engine ignition'},
{'datetime': datetime.datetime(1969, 7, 20, 20, 10, 22),
'level': 'ERROR',
'message': 'LM 1202 alarm'},
{'datetime': datetime.datetime(1969, 7, 20, 20, 14, 18),
'level': 'ERROR',
'message': 'LM 1201 alarm'},
{'datetime': datetime.datetime(1969, 7, 20, 20, 17, 39),
'level': 'WARNING',
'message': 'LM lunar landing'},
{'datetime': datetime.datetime(1969, 7, 21, 2, 39, 33),
'level': 'DEBUG',
'message': 'EVA started (hatch open)'},
{'datetime': datetime.datetime(1969, 7, 21, 2, 56, 15),
'level': 'WARNING',
'message': '1st step taken lunar surface (CDR)'},
{'datetime': datetime.datetime(1969, 7, 21, 2, 56, 15),
'level': 'WARNING',
'message': 'Neil Armstrong first words on the Moon'},
{'datetime': datetime.datetime(1969, 7, 21, 3, 5, 58),
'level': 'DEBUG',
'message': 'Contingency sample collection started (CDR)'},
{'datetime': datetime.datetime(1969, 7, 21, 3, 15, 16),
'level': 'INFO',
'message': 'LMP on lunar surface'},
{'datetime': datetime.datetime(1969, 7, 21, 5, 11, 13),
'level': 'DEBUG',
'message': 'EVA ended (hatch closed)'},
{'datetime': datetime.datetime(1969, 7, 21, 17, 54),
'level': 'WARNING',
'message': 'LM lunar liftoff ignition (LM APS)'},
{'datetime': datetime.datetime(1969, 7, 21, 21, 35),
'level': 'INFO',
'message': 'CSM/LM docked'},
{'datetime': datetime.datetime(1969, 7, 22, 4, 55, 42),
'level': 'WARNING',
'message': 'Transearth injection ignition (SPS)'},
{'datetime': datetime.datetime(1969, 7, 24, 16, 21, 12),
'level': 'INFO',
'message': 'CM/SM separation'},
{'datetime': datetime.datetime(1969, 7, 24, 16, 35, 5),
'level': 'WARNING',
'message': 'Entry'},
{'datetime': datetime.datetime(1969, 7, 24, 16, 50, 35),
'level': 'WARNING',
'message': 'Splashdown (went to apex-down)'},
{'datetime': datetime.datetime(1969, 7, 24, 17, 29),
'level': 'INFO',
'message': 'Crew egress'}]
"""
from datetime import date, datetime, time

DATA = """1969-07-14, 21:00:00, INFO, Terminal countdown started
1969-07-16, 13:31:53, WARNING, S-IC engine ignition (#5)
1969-07-16, 13:33:23, DEBUG, Maximum dynamic pressure (735.17 lb/ft^2)
1969-07-16, 13:34:44, WARNING, S-II ignition
1969-07-16, 13:35:17, DEBUG, Launch escape tower jettisoned
1969-07-16, 13:39:40, DEBUG, S-II center engine cutoff
1969-07-16, 16:22:13, INFO, Translunar injection
1969-07-16, 16:56:03, INFO, CSM docked with LM/S-IVB
1969-07-16, 17:21:50, INFO, Lunar orbit insertion ignition
1969-07-16, 21:43:36, INFO, Lunar orbit circularization ignition
1969-07-20, 17:44:00, INFO, CSM/LM undocked
1969-07-20, 20:05:05, WARNING, LM powered descent engine ignition
1969-07-20, 20:10:22, ERROR, LM 1202 alarm
1969-07-20, 20:14:18, ERROR, LM 1201 alarm
1969-07-20, 20:17:39, WARNING, LM lunar landing
1969-07-21, 02:39:33, DEBUG, EVA started (hatch open)
1969-07-21, 02:56:15, WARNING, 1st step taken lunar surface (CDR)
1969-07-21, 02:56:15, WARNING, Neil Armstrong first words on the Moon
1969-07-21, 03:05:58, DEBUG, Contingency sample collection started (CDR)
1969-07-21, 03:15:16, INFO, LMP on lunar surface
1969-07-21, 05:11:13, DEBUG, EVA ended (hatch closed)
1969-07-21, 17:54:00, WARNING, LM lunar liftoff ignition (LM APS)
1969-07-21, 21:35:00, INFO, CSM/LM docked
1969-07-22, 04:55:42, WARNING, Transearth injection ignition (SPS)
1969-07-24, 16:21:12, INFO, CM/SM separation
1969-07-24, 16:35:05, WARNING, Entry
1969-07-24, 16:50:35, WARNING, Splashdown (went to apex-down)
1969-07-24, 17:29, INFO, Crew egress"""

# Define parse() to extract date, time, level and message
# type: Callable[[str], [Log]]
def parse(line):
...

# Define result: map with parse() function applied to DATA
# type: map
result = ...


"""
* Assignment: Iterator Map CSV
* Complexity: easy
* Lines of code: 5 lines
* Time: 5 min

English:
1. Define function parse(str) -> list[tuple]
2. Define result: map with function parse() applied to DATA
3. Convert numeric values to float
4. Run doctests - all must succeed

Polish:
1. Zdefiniuj funkcję parse(str) -> list[tuple]
2. Zdefiniuj result: map z funkcją parse() zaaplikowaną do DATA
3. Przekonwertuj wartości numeryczne do float
4. Uruchom doctesty - wszystkie muszą się powieść

Hints:
* str.strip()
* str.split()
* str.splitlines()
* map()
* float()
* ('hello',) - one element tuple
* (1, 2, 3) + ('hello',) - adding tuples

Tests:
>>> import sys; sys.tracebacklimit = 0

>>> assert result is not Ellipsis, \
'Assign result to variable: result'

>>> assert type(result) is map, \
'Variable result has invalid type, should be map'

>>> result = list(result)  # expand map object
>>> assert type(result) is list, \
'Variable result has invalid type, should be list'

>>> assert all(type(x) is tuple for x in result), \
'All rows in result should be tuple'

>>> result  # doctest: +NORMALIZE_WHITESPACE
[(5.8, 2.7, 5.1, 1.9, 'virginica'),
(5.1, 3.5, 1.4, 0.2, 'setosa'),
(5.7, 2.8, 4.1, 1.3, 'versicolor')]
"""

DATA = """5.8,2.7,5.1,1.9,virginica
5.1,3.5,1.4,0.2,setosa
5.7,2.8,4.1,1.3,versicolor"""

# values from file (note the tuple format!)
# type: Callable[[str], [tuple]]
def parse(line):
...

# Define result: map with function parse() applied to DATA
# type: map
result = ...


"""
* Complexity: easy
* Lines of code: 6 lines
* Time: 8 min

English:
1. Define class_labels: list[str] from header (species names)
2. Define label_encoder: dict[int,str] converting class_labels
(species name index is the last digit in the line)
3. Define function parse(str) -> list[tuple]
4. Define result: map with function parse() applied to DATA
5. Convert numeric values to float
6. Run doctests - all must succeed

Polish:
1. Zdefiniuj class_labels: list[str] z nagłówka (nazwy gatunków)
2. Zdefiniuj label_encoder: dict[int,str] przekształcając class_labels
(indeks nazwy gatunku to ostatnia cyfra w linii)
3. Zdefiniuj funckję parse(str) -> list[tuple]
4. Zdefiniuj result: map z funkcją parse() zaaplikowaną do DATA
5. Przekonwertuj wartości numeryczne do float
6. Uruchom doctesty - wszystkie muszą się powieść

Hints:
* str.splitlines()
* str.strip()
* str.split()
* result, *others = 1, 2, 3, 4
* dict()
* enumerate()
* map()
* float()
* ('hello',) - one element tuple
* (1, 2, 3) + ('hello',) - adding tuples

Tests:
>>> import sys; sys.tracebacklimit = 0

>>> assert result is not Ellipsis, \
'Assign result to variable: result'

>>> assert type(result) is map, \
'Variable result has invalid type, should be map'

>>> result = list(result)  # expand map object
>>> assert type(result) is list, \
'Variable result has invalid type, should be list'

>>> assert all(type(x) is tuple for x in result), \
'All rows in result should be tuple'

>>> result  # doctest: +NORMALIZE_WHITESPACE
[(5.8, 2.7, 5.1, 1.9, 'virginica'),
(5.1, 3.5, 1.4, 0.2, 'setosa'),
(5.7, 2.8, 4.1, 1.3, 'versicolor')]
"""

DATA = """3,4,setosa,virginica,versicolor
5.8,2.7,5.1,1.9,1
5.1,3.5,1.4,0.2,0
5.7,2.8,4.1,1.3,2"""

label_encoder = dict(enumerate(class_labels))

# type: Callable[[str], [tuple]]
def parse(line):
...

# type: map
result = ...


"""
* Assignment: Iterator Map Parse
* Type: class assignment
* Complexity: easy
* Lines of code: 7 lines
* Time: 8 min

English:
1. Use map() to apply function convert() to DATA
2. Function convert():
a. Takes string
b. Splits string
c. Returns dict with ip and hosts as keys, example:
{'ip': '10.13.37.1', 'hosts': ['nasa.gov', 'esa.int']}
2. Define result: map with result
3. Run doctests - all must succeed

Polish:
1. Użyj map() aby zaaplikować funkcję convert() do DATA
2. Funkcja convert():
a. Przyjmuje stringa
b. Dzieli stringa
c. Zwraca dict z ip i hosts jako klucze, przykład:
{'ip': '10.13.37.1', 'hosts': ['nasa.gov', 'esa.int']}
2. Zdefiniuj result: map z wynikiem
3. Uruchom doctesty - wszystkie muszą się powieść

Hints:
* map()

Tests:
>>> import sys; sys.tracebacklimit = 0
>>> from inspect import isfunction

>>> assert isfunction(convert), \
'Object parse must be a function'

>>> assert result is not Ellipsis, \
'Assign result to variable: result'

>>> assert type(result) is map, \
'Variable result has invalid type, should be map'

>>> result = list(result)
>>> assert type(result) is list, \
'Evaluated result has invalid type, should be list'

>>> assert all(type(x) is dict for x in result), \
'All rows in result should be dict'

>>> list(result)  # doctest: +NORMALIZE_WHITESPACE
[{'ip': '127.0.0.1', 'hosts': ['localhost']},
{'ip': '127.0.0.1', 'hosts': ['astromatt']},
{'ip': '10.13.37.1', 'hosts': ['nasa.gov', 'esa.int']},
{'ip': '::1', 'hosts': ['localhost']}]
"""

DATA = """127.0.0.1       localhost
127.0.0.1       astromatt
10.13.37.1      nasa.gov esa.int
`