What is print(f”…”)
Print(f Python): The f means Formatted string literals and it’s new in Python 3.6.
The f-string was introduced(PEP 498). In short, it is a way to format your string that is more readable and fast.
Example:
The f or F in front of strings tells Python to look at the values inside {} and substitute them with the values of the variables if exist.
agent = 'James Bond'
num = 9
# old ways
print('{0} has {1} number '.format(agent, num))
# f-strings way
print(f'{agent} has {num} number')
Output:
More detail about Python f print
The variables in the curly { } braces are displayed in the output as a normal print statement. f is either lower or upper it’ll work the same.
Print F-strings are faster than the two most commonly used string old formatting methods, which are % formatting and str.format().
import datetime
today = datetime.datetime.today()
print(f"{today:%B %d, %Y}")
Output: September 09, 2021
What does ‘f’ means before a string in Python?
These are called f-strings and are quite straightforward: when using an “f” in front of a string, all the variables inside curly brackets are read and replaced by their value. For example:
age = 18
message = f"You are {age} years old"
print(message)
Output: You are 18 years old
How to escape curly brackets { } in f-strings?
Although there is a custom syntax error from the parser, the same trick works as for calling .format on regular strings.
Use double curlies:
foo = 'test'
print(f'{foo} {{bar}}')Output: test {bar}
Do comment if you have any doubts or suggestions on this Python topic.
Note: IDE: PyCharm 2021.3.3 (Community Edition)
Windows 10
Python 3.10.1
All Python Examples are in Python 3, so Maybe its different from python 2 or upgraded versions.