code: def concat(a, b):
      "Same as a + b, for a and b sequences."
      if not hasattr(a, '__getitem__'):
          msg = "'%s' object can't be concatenated" % type(a).__name__
          raise TypeError(msg)
      return a + f concat(a, b):
      "Same as a + b, for a and b sequences."
      if not hasattr(a, '__getitem__'):
          msg = "'%s' object can't be concatenated" % type(a).__name__
          raise TypeError(msg)
      return a + b
docs: Same as a + b, for a and b sequences.