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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 parse_var(var):
 """ Returns a tuple consisting of a string and a tag, or None, if none is specified. """

    bits = var.split("<", 1)
    if len(bits) < 2:
        tag = None
    else:
        tag = bits[1]
    return ucn_to_unicode(bits[0]), tag