<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def add_access_key_permissions(self, access_key_id, permissions):
 """ Adds to the existing list of permissions on this key with the contents of this list. Will not remove any existing permissions or modify the remainder of the key. :param access_key_id: the 'key' value of the access key to add permissions to :param permissions: the new permissions to add to the existing list of permissions """

        # Get current state via HTTPS.
        current_access_key = self.get_access_key(access_key_id)

        # Copy and only change the single parameter.
        payload_dict = KeenApi._build_access_key_dict(current_access_key)

        # Turn into sets to avoid duplicates.
        old_permissions = set(payload_dict["permitted"])
        new_permissions = set(permissions)
        combined_permissions = old_permissions.union(new_permissions)
        payload_dict["permitted"] = list(combined_permissions)

        # Now just treat it like a full update.
        return self.update_access_key_full(access_key_id, **payload_dict)