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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 is_position_aes(vars_):
 """ Figure out if an aesthetic is a position aesthetic or not """

    try:
        return all([aes_to_scale(v) in {'x', 'y'} for v in vars_])
    except TypeError:
        return aes_to_scale(vars_) in {'x', 'y'}