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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_intensity_col(data):
 """ Check measurement dataframe for intensity columns 'magn_moment', 'magn_volume', 'magn_mass','magn_uncal'. Return the first intensity column that is in the dataframe AND has data. Parameters data : pandas DataFrame Returns --------- str intensity method column or "" """

    # possible intensity columns
    intlist = ['magn_moment', 'magn_volume', 'magn_mass','magn_uncal']
    # intensity columns that are in the data
    int_meths = [col_name for col_name in data.columns if col_name in intlist]
    # drop fully null columns
    data.dropna(axis='columns', how='all')
    # ignore columns with only blank values (including "")
    for col_name in int_meths[:]:
        if not data[col_name].any():
            int_meths.remove(col_name)
    if len(int_meths):
        if 'magn_moment' in int_meths:
            return 'magn_moment'
        return int_meths[0]
    return ""