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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 format_data(data):
 """ Format bytes for printing :param data: Bytes :type data: None | bytearray | str :return: Printable version :rtype: unicode """

    if data is None:
        return None
    return u":".join([u"{:02x}".format(ord(c)) for c in data])