fastest way to check if a string is in another string python code example

Example 1: python string contains

>>> str = "Messi is the best soccer player"
>>> "soccer" in str
True
>>> "football" in str
False

Example 2: how to check for a substring in python

def find_string(string,sub_string):
	return string.find(sub_string)
#.find() also accounts for multiple occurence of the substring in the given string