Python - Compare 2 words and check if they are anagram

I am trying to define a function that takes 2 strings, compare those two and returns True if they are anagram. I don't want to import collections.

So, if string1 is python and string 2 is nohtyp, it should return True. Otherwise, obviously, return false. Here's my code looks like so far:

def check_anagram(str1, str2):
if len(str1) != len(str2):
    return False
else:
    for i in range(0, len(str1), 1):
        if i in range(0, len(str2), 1):
            return True
        else:
            return False

It works well for most of cases, but when str1 is aaaaaaaaaabbbbbbbbbb and str2 is ababababbbababababab, it returns true and when str1 is xxxyyyxxx and str2 is yyyxxxyyy, it also returns True.

It should retrun False for these 2 cases, but I have no idea. Can anybody help me with this?

I think the most trivial way to do the task is sorting your strings and comparing them like this example:

def check_anagram(a = '', b = ''):
    return sorted(a) == sorted(b)

Test1:

a = "python"
b = "nohtyp"
print(check_anagram(a, b))

Output:

>>> True

Test2:

a = "aaaaaaaaaabbbbbbbbb"
b = "ababababbbababababab"
print(check_anagram(a, b))

Output:

>>> False

Test3:

a = "xxxyyyxxx"
b = "yyyxxxyyy"
print(check_anagram(a, b))

Output:

>>> False