code: def create_backend(self, 
  		service_id,
  		version_number, 
  		name, 
  		address,
  		use_ssl=False,
  		port=80,
  		connect_timeout=1000,
  		first_byte_timeout=15000,
  		between_bytes_timeout=10000,
  		error_threshold=0,
  		max_conn=20,
  		weight=100,
  		auto_loadbalance=False,
  		shield=None,
  		request_condition=None,
  		healthcheck=None,
  		comment=None):
  		
  		body = self._formdata({
  			"name": name,
  			"address": address,
  			"use_ssl": use_ssl,
  			"port": port,
  			"connect_timeout": connect_timeout,
  			"first_byte_timeout": first_byte_timeout,
  			"between_bytes_timeout": between_bytes_timeout,
  			"error_threshold": error_threshold,
  			"max_conn": max_conn,
  			"weight": weight,
  			"auto_loadbalance": auto_loadbalance,
  			"shield": shield,
  			"request_condition": request_condition,
  			"healthcheck": healthcheck,
  			"comment": comment,
  		}, FastlyBackend.FIELDS)
  		content = self._fetch("/service/%s/version/%d/backend" % (service_id, version_number), method="POST", body=body)
  		return FastlyBackend(self, content)
docs: Create a backend for a particular service and version.