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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 primary_keys_full(cls):
 """Get primary key properties for a SQLAlchemy cls. Taken from marshmallow_sqlalchemy """

        mapper = cls.__mapper__
        return [
            mapper.get_property_by_column(column)
            for column in mapper.primary_key
        ]