Given 2 strings, your job is to find out if there is a substring that appears in both strings. You will return true if you find a substring that appears in both strings, or false if you do not. We only care about substrings that are longer than one letter long.
#Examples:
````
*Example 1*
SubstringTest("Something","Fun"); //Returns false
*Example 2*
SubstringTest("Something","Home"); //Returns true
````
In the above example, example 2 returns true because both of the inputs contain the substring "me". (so**ME**thing and ho**ME**)  
In example 1, the method will return false because something and fun contain no common substrings. (We do not count the 'n' as a substring in this Kata because it is only 1 character long)
#Rules:
Lowercase and uppercase letters are the same. So 'A' == 'a'.  
We only count substrings that are > 1 in length.  
#Input:
Two strings with both lower and upper cases.
#Output:
A boolean value determining if there is a common substring between the two inputs.
def substring_test(str1, str2):
    str1,str2 = str1.lower(),str2.lower()
    s1 = [str1[i:i+2] for i in range(len(str1)-1)]
    s2 = [str2[i:i+2] for i in range(len(str2)-1)]
    return len(set(s1).intersection(s2))>0
def substring_test(str1, str2):
    str1,str2 = str1.lower(),str2.lower()
    s1 = [str1[i:i+2] for i in range(len(str1)-1)]
    s2 = [str2[i:i+2] for i in range(len(str2)-1)]
    return len(set(s1).intersection(s2))>0