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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:
 def user(session, uid, ladder_ids=None):
 """Get all possible user info by name."""

    data = get_user(session, uid)
    resp = dict(data)
    if not ladder_ids:
        return resp
    resp['ladders'] = {}
    for ladder_id in ladder_ids:
        if isinstance(ladder_id, str):
            ladder_id = lookup_ladder_id(ladder_id)
        try:
            ladder_data = dict(get_ladder(session, ladder_id, user_id=uid))
            resp['ladders'][ladder_id] = ladder_data
        except VooblyError:
            # No ranking on ladder
            pass
    return resp