def list_device_data_sources(self, device_rid):
headers = {<EOL>'<STR_LIT>': self.user_agent(),<EOL>}<EOL>headers.update(self.headers())<EOL>r = requests.get(   self.portals_url()+'<STR_LIT>'+device_rid+'<STR_LIT>', <EOL>headers=headers, auth=self.auth())<EOL>if HTTP_STATUS.OK == r.status_code:<EOL><INDENT>return r.json()<EOL><DEDENT>else:<EOL><INDENT>print("<STR_LIT>".format(<EOL>r.status_code, r.reason))<EOL>return None<EOL><DEDENT>
List data sources of a portal device with rid 'device_rid'.

http://docs.exosite.com/portals/#list-device-data-source