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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 infer_calendar_name(dates):
 """Given an array of datetimes, infer the CF calendar name"""

    if np.asarray(dates).dtype == 'datetime64[ns]':
        return 'proleptic_gregorian'
    else:
        return np.asarray(dates).ravel()[0].calendar