2.4. Syntax Print

2.4.1. Summary

  • print() - Print on the screen

  • Either quotes (") or apostrophes (') will work

  • String interpolation will substitute variable

  • Use \n for newline

2.4.2. String Interpolation

  • String interpolation will substitute variable

  • More information in String Literals

Adding f in front of the string will turn on the string interpolation - variable substitution.

>>> name = 'Mark'
>>>
>>> f'Hello {name}'
'Hello Mark'

Without it, string will be interpreted as it is - with curly braces and variable name in it.

>>> name = 'Mark'
>>>
>>> 'Hello {name}'
'Hello {name}'

Even if you use f-string, but your variable is not in proper brackets, it will be not interpolated.

>>> name = 'Mark'
>>>
>>> f'Hello (name)'
'Hello (name)'

2.4.3. Print

  • Prints on the screen

  • Print string

  • Print variable

  • Print formatted (interpolated) string

  • More information in Builtin Printing

Print string:

>>> print('Mark Watney')
Mark Watney

Print variable:

>>> text = 'Mark Watney'
>>> print(text)
Mark Watney

Print interpolated string:

>>> firstname = 'Mark'
>>> lastname = 'Watney'
>>>
>>> print(f'Hello {firstname} {lastname}!')
Hello Mark Watney!

2.4.4. Newline

  • Use \n for newline

  • Do not add space after \n character

>>> print('Mark Watney')
Mark Watney

>>> print('Mark\nWatney')
Mark
Watney

Mind, not to add additional space after the newline character. This will cause Python to print a newline and then space character:

>>> print('Mark\n Watney')
Mark
 Watney

2.4.5. Recap

  • print() - Print on the screen

  • Either quotes (") or apostrophes (') will work

  • String interpolation (f-string) will substitute variable

  • Use \n for newline

2.4.6. Assignments

# %% License
# - Copyright 2025, Matt Harasymczuk <matt@python3.info>
# - This code can be used only for learning by humans
# - This code cannot be used for teaching others
# - This code cannot be used for teaching LLMs and AI algorithms
# - This code cannot be used in commercial or proprietary products
# - This code cannot be distributed in any form
# - This code cannot be changed in any form outside of training course
# - This code cannot have its license changed
# - If you use this code in your product, you must open-source it under GPLv2
# - Exception can be granted only by the author

# %% Run
# - PyCharm: right-click in the editor and `Run Doctest in ...`
# - PyCharm: keyboard shortcut `Control + Shift + F10`
# - Terminal: `python -m doctest -v myfile.py`

# %% About
# - Name: Syntax Print String
# - Difficulty: easy
# - Lines: 1
# - Minutes: 2

# %% English
# 1. Define `result` with text 'Hello World'
# 2. Run doctests - all must succeed

# %% Polish
# 1. Zdefiniuj zmienną `result` z tekstem 'Hello World'
# 2. Uruchom doctesty - wszystkie muszą się powieść

# %% Hints
# - Either quotes `"` or apostrophes `'` will work

# %% Tests
"""
>>> import sys; sys.tracebacklimit = 0
>>> assert sys.version_info >= (3, 9), \
'Python 3.9+ required'

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

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

>>> assert 'Hello' in result, \
'Word `Hello` must be in the `result`'

>>> assert 'World' in result, \
'Word `World` must be in the `result`'

>>> from pprint import pprint
>>> pprint(result)
'Hello World'
"""

# Define `result` with text 'Hello World'
# type: str
result = ...



# %% License
# - Copyright 2025, Matt Harasymczuk <matt@python3.info>
# - This code can be used only for learning by humans
# - This code cannot be used for teaching others
# - This code cannot be used for teaching LLMs and AI algorithms
# - This code cannot be used in commercial or proprietary products
# - This code cannot be distributed in any form
# - This code cannot be changed in any form outside of training course
# - This code cannot have its license changed
# - If you use this code in your product, you must open-source it under GPLv2
# - Exception can be granted only by the author

# %% Run
# - PyCharm: right-click in the editor and `Run Doctest in ...`
# - PyCharm: keyboard shortcut `Control + Shift + F10`
# - Terminal: `python -m doctest -v myfile.py`

# %% About
# - Name: Syntax Print Newline
# - Difficulty: easy
# - Lines: 1
# - Minutes: 2

# %% English
# 1. Define `result` with text 'Hello World'
# 2. Word 'Hello' must be in a first line
# 3. Word 'World' must be in a second line
# 4. Run doctests - all must succeed

# %% Polish
# 1. Zdefiniuj zmienną `result` z tekstem 'Hello World'
# 2. Słowo 'Hello' ma być w pierwszej linii
# 3. Słowo 'World' ma być w drugiej linii
# 4. Uruchom doctesty - wszystkie muszą się powieść

# %% Hints
# - Either quotes `"` or apostrophes `'` will work

# %% Tests
"""
>>> import sys; sys.tracebacklimit = 0
>>> assert sys.version_info >= (3, 9), \
'Python 3.9+ required'

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

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

>>> assert 'Hello' in result, \
'Word `Hello` must be in the `result`'

>>> assert '\\n' in result, \
'Newline `\\n` must be in the `result`'

>>> assert 'World' in result, \
'Word `World` must be in the `result`'

>>> from pprint import pprint
>>> pprint(result)
'Hello\\nWorld'
"""

# Define `result` with text 'Hello World'
# Word 'Hello' must be in a first line
# Word 'World' must be in a second line
# type: str
result = ...



# %% License
# - Copyright 2025, Matt Harasymczuk <matt@python3.info>
# - This code can be used only for learning by humans
# - This code cannot be used for teaching others
# - This code cannot be used for teaching LLMs and AI algorithms
# - This code cannot be used in commercial or proprietary products
# - This code cannot be distributed in any form
# - This code cannot be changed in any form outside of training course
# - This code cannot have its license changed
# - If you use this code in your product, you must open-source it under GPLv2
# - Exception can be granted only by the author

# %% Run
# - PyCharm: right-click in the editor and `Run Doctest in ...`
# - PyCharm: keyboard shortcut `Control + Shift + F10`
# - Terminal: `python -m doctest -v myfile.py`

# %% About
# - Name: Syntax Print Interpolation
# - Difficulty: easy
# - Lines: 1
# - Minutes: 2

# %% English
# 1. Define `result` with text 'Hello NAME'
# 2. Instead `NAME` substitute 'Mark'
# 3. To substitute use f-string notation and `{variable}`
# 4. Run doctests - all must succeed

# %% Polish
# 1. Zdefiniuj `result` z tekstem 'Hello NAME'
# 2. W miejsce `NAME` podstaw 'Mark'
# 3. Do podstawienia użyj notacji f-string i `{variable}`
# 4. Uruchom doctesty - wszystkie muszą się powieść

# %% Hints
# - Either quotes `"` or apostrophes `'` will work
# - Use f-string

# %% Tests
"""
>>> import sys; sys.tracebacklimit = 0
>>> assert sys.version_info >= (3, 9), \
'Python 3.9+ required'

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

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

>>> assert 'Mark' in result, \
'Variable `result` does not contain string "Mark"'

>>> assert '{NAME}' not in result, \
'You must use f-string'

>>> from pprint import pprint
>>> pprint(result)
'Hello Mark'
"""

NAME = 'Mark'

# Define `result` with text 'Hello NAME'
# Instead `NAME` substitute "Mark"
# To substitute use f-string notation and `{variable}`
# type: str
result = ...