Palindromic sub-sequences in python

This bit of code returns all palindromic subsequences in the input string. If the line marked #In-efficient is better implemented (I am lazy), the running time is O(n2). Can you find a better solution?

palindrome.py
 1 #!/usr/bin/env python
 2 
 3 def get_palindromes(str):
 4     """ Return all palindromes in str of minimum size 3 """
 5     length = len(str) + 1
 6     
 7     found = []
 8     for i in xrange(0, length):
 9         for j in xrange(i+3, length):
10             mid = i + ((j - i) / 2)
11             if str[i:mid] == str[mid+1:j][::-1]: # In-efficient
12                 found.append(str[i:j])
13     return found    
14 
15 if __name__ == '__main__':
16     print get_palindromes('efeababaf')