What are docstrings in Python?

• Python documentation strings (or docstrings). It is used like a comment, to document a specific segment of code.

• The docstring should describe what the function does, not how.

• It must be the first statement in the object’s definition.

• It begins with a capital letter and ends with a period.

• They are declared using ‘'’triple single quotes’’’ or “"”triple double quotes”””.

Example:

def decrement(number):
    """This is the docstring of this function.
    
    It describes what the function does, what are its calling conventions and
        what are its side effects"""
    number=number-1
    return number

Additional information

Comments vs. docstrings

Both are written using multiline strings but they are not completely same:

Comment - This are used to increase the understandability of the code and they generally explain why a statement has been used in the program.

Docstring -This are used to associate the documentation with the objects like classes, methods and functions in python and they describe what the object does.

References

Docstrings

Comments vs. docstrings - examples