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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 convert_unicode_field(string):
 """ Convert a Unicode field into the corresponding list of Unicode strings. The (input) Unicode field is a Unicode string containing one or more Unicode codepoints (``xxxx`` or ``U+xxxx`` or ``xxxx_yyyy``), separated by a space. :param str string: the (input) Unicode field :rtype: list of Unicode strings """

    values = []
    for codepoint in [s for s in string.split(DATA_FILE_CODEPOINT_SEPARATOR) if (s != DATA_FILE_VALUE_NOT_AVAILABLE) and (len(s) > 0)]:
        values.append(u"".join([hex_to_unichr(c) for c in codepoint.split(DATA_FILE_CODEPOINT_JOINER)]))
    return values