Add roles to a member

        This method takes a list of **role ids** that you want to give to the user,
        on top of whatever roles they may already have. This method will fetch
        the user's current roles, and add to that list the roles passed in. The
        user's resulting list of roles will not contain duplicates, so you don't have
        to filter role ids to this method (as long as they're still roles for this guild).

        This method differs from ``set_member_roles`` in that this method ADDS roles
        to the user's current role list. ``set_member_roles`` is used by this method.

        Args:
            guild_id: snowflake id of the guild
            member_id: snowflake id of the member
            roles: list of snowflake ids of roles to add

def add_member_roles(self, guild_id: int, member_id: int, roles: List[int]):
        """Add roles to a member

        This method takes a list of **role ids** that you want to give to the user,
        on top of whatever roles they may already have. This method will fetch
        the user's current roles, and add to that list the roles passed in. The
        user's resulting list of roles will not contain duplicates, so you don't have
        to filter role ids to this method (as long as they're still roles for this guild).

        This method differs from ``set_member_roles`` in that this method ADDS roles
        to the user's current role list. ``set_member_roles`` is used by this method.

        Args:
            guild_id: snowflake id of the guild
            member_id: snowflake id of the member
            roles: list of snowflake ids of roles to add
        """
        current_roles = [role for role in self.get_guild_member_by_id(guild_id, member_id)['roles']]
        roles.extend(current_roles)
        new_list = list(set(roles))
        self.set_member_roles(guild_id, member_id, new_list)