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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_imperial():
 """Return array of possible drill diameters in imperial."""

    step_32nd = np.arange(0.03125, 0.25, 0.03125)
    step_8th = np.arange(0.25, 1.0, 0.125)
    step_4th = np.arange(1.0, 2.0, 0.25)
    maximum = [2.0]

    return np.concatenate((step_32nd,
                           step_8th,
                           step_4th,
                           maximum)) * u.inch