Not sure if this is acceptable,since permuting long strings may not work(Memory Limit/Time Limit), but this is one of the ways to find whether the given string one of it's permutations.Can also be used to generate power-set for a given string of length n

```
class Solution(object):
def isScramble(self, s1, s2):
#assuming strings passed are of equal length, else corner case
if(len(s1)!=len(s2)):
return
e = []
for a in itertools.permutations(s1,len(s1)):
e.append("".join(a))
if s2 in e:
return True
else:
return False
```