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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 clean_path(root, path, subdir=False):
    '''
    Accepts the root the path needs to be under and verifies that the path is
    under said root. Pass in subdir=True if the path can result in a
    subdirectory of the root instead of having to reside directly in the root
    '''
    if not os.path.isabs(root):
        return ''
    if not os.path.isabs(path):
        path = os.path.join(root, path)
    path = os.path.normpath(path)
    if subdir:
        if path.startswith(root):
            return path
    else:
        if os.path.dirname(path) == os.path.normpath(root):
            return path
    return ''