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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 _partition(entity, sep):
 """Python2.4 doesn't have a partition method so we provide our own that mimics str.partition from later releases. Split the string at the first occurrence of sep, and return a 3-tuple containing the part before the separator, the separator itself, and the part after the separator. If the separator is not found, return a 3-tuple containing the string itself, followed by two empty strings. """

    parts = entity.split(sep, 1)
    if len(parts) == 2:
        return parts[0], sep, parts[1]
    else:
        return entity, '', ''