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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 get_drill_bits_d_metric():
 """Return array of possible drill diameters in metric."""

    return np.concatenate((np.arange(1.0, 10.0, 0.1),
                           np.arange(10.0, 18.0, 0.5),
                           np.arange(18.0, 36.0, 1.0),
                           np.arange(40.0, 55.0, 5.0))) * u.mm