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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_tenant_url(url_string):
 """ Removes the TENANT_TOKEN from a particular string """

    if hasattr(settings, 'PUBLIC_SCHEMA_URLCONF'):
        if (settings.PUBLIC_SCHEMA_URLCONF and
                url_string.startswith(settings.PUBLIC_SCHEMA_URLCONF)):
            url_string = url_string[len(settings.PUBLIC_SCHEMA_URLCONF):]
    return url_string