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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 select_extended(cat_table):
 """Select only rows representing extended sources from a catalog table """

    try:
        l = [len(row.strip()) > 0 for row in cat_table['Extended_Source_Name'].data]
        return np.array(l, bool)
    except KeyError:
        return cat_table['Extended']