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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 async def _trim_old_connections( new_name: str, con_type: CONNECTION_TYPES) -> Tuple[bool, str]: """ Delete all connections of con_type but the one specified. """

    existing_cons = await connections(for_type=con_type)
    not_us = [c['name'] for c in existing_cons if c['name'] != new_name]
    ok = True
    res = []
    for c in not_us:
        this_ok, remove_res = await remove(name=c)
        ok = ok and this_ok
        if not this_ok:
            # This is not a failure case for connection, and indeed the new
            # connection is already established, so just warn about it
            log.warning("Could not remove wifi connection {}: {}"
                        .format(c, remove_res))
            res.append(remove_res)
        else:
            log.debug("Removed old wifi connection {}".format(c))
    return ok, ';'.join(res)