下列代码中，使用了requests的Session对象，并调用prepare_request()为使prepped为赋值。有关Prepped这个对象的作用，下列描述最为符合的是（ ）。from requests import Request, Sessions = Session()req = Request('GET', url, data=data, headers=headers)prepped = s.prepare_request(req)# do something with prepped.bodyprepped.body = 'Seriously, send exactly these bytes.'# do something with prepped.headersprepped.headers['Keep-Dead'] = 'parrot'resp = s.send(prepped, stream=stream, verify=verify, proxies=proxies, cert=cert, timeout=timeout)print(resp.status_code)