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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_closest_dt_idx(dt, dt_list):
 """Get indices of dt_list that is closest to input dt """

    from pygeotools.lib import malib
    dt_list = malib.checkma(dt_list, fix=False)
    dt_diff = np.abs(dt - dt_list)
    return dt_diff.argmin()