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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 execute_cast_timestamp_to_timestamp(op, data, type, **kwargs):
 """Cast timestamps to other timestamps including timezone if necessary"""

    input_timezone = data.tz
    target_timezone = type.timezone

    if input_timezone == target_timezone:
        return data

    if input_timezone is None or target_timezone is None:
        return data.tz_localize(target_timezone)

    return data.tz_convert(target_timezone)