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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 na_if(series, *values):
 """ If values in a series match a specified value, change them to `np.nan`. Args: series: Series or vector, often symbolic. *values: Value(s) to convert to `np.nan` in the series. """


    series = pd.Series(series)
    series[series.isin(values)] = np.nan
    return series