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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 copy_layer_keywords(layer_keywords):
 """Helper to make a deep copy of a layer keywords. :param layer_keywords: A dictionary of layer's keywords. :type layer_keywords: dict :returns: A deep copy of layer keywords. :rtype: dict """

    copy_keywords = {}
    for key, value in list(layer_keywords.items()):
        if isinstance(value, QUrl):
            copy_keywords[key] = value.toString()
        elif isinstance(value, datetime):
            copy_keywords[key] = value.date().isoformat()
        elif isinstance(value, QDate):
            copy_keywords[key] = value.toString(Qt.ISODate)
        elif isinstance(value, QDateTime):
            copy_keywords[key] = value.toString(Qt.ISODate)
        elif isinstance(value, date):
            copy_keywords[key] = value.isoformat()
        else:
            copy_keywords[key] = deepcopy(value)

    return copy_keywords