docs: async def set_access_string(self, **params):
  		"""Writes content access string to database 
  		"""
  		if params.get("message"):
  			params = json.loads(params.get("message", "{}"))
  
  		cid = int(params.get("cid", "0"))
  		seller_access_string = params.get("seller_access_string")
  		seller_pubkey = params.get("seller_pubkey")
  		coinid = params.get("coinid")
  
  		try:
  			coinid = coinid.replace("TEST", "")
  		except:
  			pass
  
  		database = client[coinid]
  		collection = database[settings.CONTENT]
  		content = await collection.find_one({"cid":cid})
  
  		if not content:
  			return {"error":404, "reason":"Content not found"}
  
  		if not all([cid, seller_access_string, seller_pubkey]):
  			return {"error":400, "reason":"Missed required fields"}
  
  		await collection.find_one_and_update({"cid":cid},
  						{"$set":{"seller_access_string":seller_access_string}})
  
  		await collection.find_one_and_update({"cid":cid},
  						{"$set":{"seller_pubkey":seller_pubkey}})
  
  		content = await collection.find_one({"cid":cid})
  		return {i:content[i] for i in content if i != "_id"}