code: def add_member_roles(self, guild_id: int, member_id: int, roles: List[int]):
          
          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)
docs: 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