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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 _list_dir(self, path):
 """returns absolute paths for all entries in a directory"""

        try:
            elements = [
                os.path.join(path, x) for x in os.listdir(path)
            ] if os.path.isdir(path) else []
            elements.sort()
        except OSError:
            elements = None
        return elements