change getNum function providers

            return "Error when retreiving provider list: ", e

    def get_num_providers(self):

        mycol = self.db.get_col_by_name(self.db.providers)

        user_col = self.db.get_col_by_name_register(self.db.user)

        try:

            users = user_col.find({}, {"_id": 0})

            providers = mycol.find({}, {"_id": 0})

            json_providers = []

            for provider in providers:

                # user = user_col.find({

                # "list_providers": provider["api_prov_dom_id"]

                # }, 

                # {"_id": 0})

                # provider.update(user)

                for user in users:

                    if provider["api_prov_dom_id"] in user["list_providers"]:

                        provider["username"]=user["username"]

                json_providers.append(provider)

            #return jsonify(message="Providers retrieved succesfully",

            #               object=json_providers), 200

            #return jsonify(json_providers), 200

        json_providers = Operations.get_providers()

        num_providers = len(json_providers)

        return jsonify(num_providers), 200

        except Exception as e:

            return "Error when retreiving provider list: ", e

    def get_provider_services(self, id):