code: def post_documents(self, content_type: str, consent_id: str) -> dict:
          
  
          body = json.dumps({'contentType': content_type, 'consentId': consent_id}).encode()
          uri, headers = self._create_signing_headers('POST', '/documents', body)
  
          post_documents_response = requests.post(
              url=uri.geturl(),
              headers=headers,
              data=body
          )
  
          response = _json_decode(post_documents_response)
          return response
docs: Creates a document handle, calls the POST /documents endpoint.
  
          >>> from las import Client
          >>> client = Client(endpoint='<api endpoint>')
          >>> client.post_documents('image/jpeg', consent_id='foobar')
  
          :param content_type: A mime type for the document handle
          :type content_type: str
          :param consent_id: An identifier to mark the owner of the document handle
          :type consent_id: str
          :return: Document handle id and pre-signed upload url
          :rtype: dict
          :raises InvalidCredentialsException: If the credentials are invalid
          :raises TooManyRequestsException: If limit of requests per second is reached
          :raises LimitExceededException: If limit of total requests per month is reached
          :raises requests.exception.RequestException: If error was raised by requests