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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_col_epsg(mapped_class, geom_attr):
 """Get the EPSG code associated with a geometry attribute. Arguments: geom_attr the key of the geometry property as defined in the SQLAlchemy mapper. If you use ``declarative_base`` this is the name of the geometry attribute as defined in the mapped class. """

    col = class_mapper(mapped_class).get_property(geom_attr).columns[0]
    return col.type.srid