code: def _create_modulename(cdef_sources, source, sys_version):
      
      key = '\x00'.join([sys_version[:3], source, cdef_sources])
      key = key.encode('utf-8')
      k1 = hex(binascii.crc32(key[0::2]) & 0xffffffff)
      k1 = k1.lstrip('0x').rstrip('L')
      k2 = hex(binascii.crc32(key[1::2]) & 0xffffffff)
      k2 = k2.lstrip('0').rstrip('L')
      return '_xprintidle_cffi_{0}{1}'.format(k1, k2)
docs: This is the same as CFFI's create modulename except we don't include the
      CFFI version.