f-strings

Available in Python version 3.6 and above.
To avoid string concatenations, we can use f-string to 'inject' values within a string via variables.

Pre-pending an f before a string will cause the variable between {} to be evaluated.

# f-strings year = 2020 print(f"The year is {year}") print(f'The year is {year}') question = f"Which year comes after {year}?" print(question) 

Updating the variable after 'f-string' has been evaluated.

Since the f-string has been evaluated with the variable year set to 2020. Re-assigning it to a new value 9999 afterwards will not update the f-string automatically.

# f-strings # Updating variable value after assignment. year = 2020 message = f"The year is {year}." print(message) year = 9999 print(message) 

Using string.format()

Another way of formatting a string is by using string.format().
Passing the variable name to format(name), will inject its value into the {} of the variable template.

name = 'Rishi' template = 'How are you {}?' fomatted_greeting = template.format(name) print(fomatted_greeting) name = 'Abee' fomatted_greeting = template.format(name) print(fomatted_greeting) 

Using named variables

Using named variables makes the template more readable.

name1 = 'Rishi' name2 = 'Abee' template = 'How are you {x} {y}?' fomatted_greeting = template.format(x=name1, y=name2) print(fomatted_greeting) 

f-strings v/s string.format()

f-strings is very common in Python.
But if you have a template and you want to re-use it, string.format() comes in very handy.