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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def TypeUrlToMessage(type_url):
 """Returns a message instance corresponding to a given type URL."""


  if not type_url.startswith(TYPE_URL_PREFIX):
    raise ValueError("Type URL has to start with a prefix %s: %s" %
                     (TYPE_URL_PREFIX, type_url))

  full_name = type_url[len(TYPE_URL_PREFIX):]
  try:
    return symbol_database.Default().GetSymbol(full_name)()
  except KeyError as e:
    raise ProtobufTypeNotFound(str(e))