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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 ID_colored_tube(color):
 """Look up the inner diameter of Ismatec 3-stop tubing given its color code. :param color: Color of the 3-stop tubing :type color: string :returns: Inner diameter of the 3-stop tubing (mm) :rtype: float :Examples: <Quantity(1.52, 'millimeter')> <Quantity(0.51, 'millimeter')> <Quantity(2.79, 'millimeter')> """

    tubing_data_path = os.path.join(os.path.dirname(__file__), "data",
        "3_stop_tubing.txt")
    df = pd.read_csv(tubing_data_path, delimiter='\t')
    idx = df["Color"] == color
    return df[idx]['Diameter (mm)'].values[0] * u.mm