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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_property_columns(tabletype, columns):
 """Returns list of GPS columns required to read gpsproperties for a table Examples -------- ['peak_time', 'peak_time_ns'] """

    from ligo.lw.lsctables import gpsproperty as GpsProperty
    # get properties for row object
    rowvars = vars(tabletype.RowType)
    # build list of real column names for fancy properties
    extracols = {}
    for key in columns:
        prop = rowvars[key]
        if isinstance(prop, GpsProperty):
            extracols[key] = (prop.s_name, prop.ns_name)
    return extracols