code: def _default_hashfunc(content, hashbits):
      
      if content == "":
          return 0
  
      x = ord(content[0]) << 7
      m = 1000003
      mask = 2 ** hashbits - 1
      for c in content:
          x = ((x * m) ^ ord(c)) & mask
      x ^= len(content)
      if x == -1:
          x = -2
      return x
docs: Default hash function is variable-length version of Python's builtin hash.
  
      :param content: data that needs to hash.
      :return: return a decimal number.