parameters: (self, s, t)
return_statement: return True
docstring: :type s: str
          :type t: str
          :rtype: bool
docstring_summary: :type s: str
          :type t: str
          :rtype: bool
docstring_tokens: : type s : str : type t : str : rtype : bool
function: def isIsomorphic(self, s, t):
          """
          :type s: str
          :type t: str
          :rtype: bool
          """
      
          if s is None or t is None or len(s) != len(t):
              return False
  
          left_to_right = {}
          right_to_left = {}
  
          for i in range(len(s)):
              if s[i] not in left_to_right:
                  left_to_right[s[i]] = t[i]
              elif left_to_right[s[i]] != t[i]:
                  return False
  
              if t[i] not in right_to_left:
                  right_to_left[t[i]] = s[i]
              elif right_to_left[t[i]] != s[i]:
                  return False
          
          return True
function_tokens: def isIsomorphic ( self , s , t ) : if s is None or t is None or len ( s ) != len ( t ) : return False left_to_right = { } right_to_left = { } for i in range ( len ( s ) ) : if s [ i ] not in left_to_right : left_to_right [ s [ i ] ] = t [ i ] elif left_to_right [ s [ i ] ] != t [ i ] : return False if t [ i ] not in right_to_left : right_to_left [ t [ i ] ] = s [ i ] elif right_to_left [ t [ i ] ] != s [ i ] : return False return True