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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 walk_up_dirs(path):
 """Yields absolute directories starting with the given path, and iterating up through all it's parents, until it reaches a root directory"""

    prev_path = None
    current_path = os.path.abspath(path)
    while current_path != prev_path:
        yield current_path
        prev_path = current_path
        current_path = os.path.dirname(prev_path)