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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 register_fields(w):
 """ Register shapefile fields. """

    PARAMS_LIST = [BASE_PARAMS, GEOMETRY_PARAMS, MFD_PARAMS]
    for PARAMS in PARAMS_LIST:
        for _, param, dtype in PARAMS:
            w.field(param, fieldType=dtype, size=FIELD_SIZE)

    PARAMS_LIST = [
        RATE_PARAMS, STRIKE_PARAMS, DIP_PARAMS, RAKE_PARAMS, NPW_PARAMS,
        HDEPTH_PARAMS, HDW_PARAMS, PLANES_STRIKES_PARAM, PLANES_DIPS_PARAM]
    for PARAMS in PARAMS_LIST:
        for param, dtype in PARAMS:
            w.field(param, fieldType=dtype, size=FIELD_SIZE)

    # source typology
    w.field('sourcetype', 'C')