Python check if string contains only certain characters code example

Example 1: how to check if all characters in string are same python

s == len(s) * s[0]

Example 2: if substring not in string python

fullstring = "StackAbuse"
substring = "tack"

if fullstring.find(substring) != -1:
    print "Found!"
else:
    print "Not found!"

Example 3: python if string contains char

myString = "<text contains this>"
myOtherString = "AnotherString"

# Casting to string is not needed but it's good practice
# to check for errors 

if str(myString) in str(myOtherString): 
    # Do Something
else:
	# myOtherString didn't contain myString

Example 4: python check if string contains one of characters list

if any(ext in url_string for ext in extensionsToCheck):
    print(url_string)