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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 _clean_dict(target_dict, whitelist=None):
 """ Convenience function that removes a dicts keys that have falsy values """

    assert isinstance(target_dict, dict)
    return {
        ustr(k).strip(): ustr(v).strip()
        for k, v in target_dict.items()
        if v not in (None, Ellipsis, [], (), "")
        and (not whitelist or k in whitelist)
    }