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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 _freezer_lookup(freezer_string):
 """ Translate a string that may be a freezer name into the internal freezer constant :param freezer_string :return: """

    sanitized = freezer_string.lower().strip()
    for freezer in FREEZER.ALL:
        freezer_instance = freezer()
        freezer_name = six.text_type(freezer_instance)
        if freezer_name == six.text_type(sanitized):
            return freezer
    else:
        if sanitized != freezer_string:
            raise ValueError(u"Unsupported freezer type \"{0}\". (Sanitized to \"{1}\")".format(freezer_string,
                                                                                              sanitized))
        else:
            raise ValueError(u"Unsupported freezer type \"{0}\".".format(freezer_string))