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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 change_column_name( conn, table, old_column_name, new_column_name, schema=None ):
 """ Changes given `activity` jsonb data column key. This function is useful when you want to reflect column name changes to activity table. :: from alembic import op from postgresql_audit import change_column_name def upgrade():
 op.alter_column( 'my_table', 'my_column', new_column_name='some_column' ) change_column_name(op, 'my_table', 'my_column', 'some_column') :param conn: An object that is able to execute SQL (either SQLAlchemy Connection, Engine or Alembic Operations object) :param table: The table to run the column name changes against :param old_column_name: Name of the column to change :param new_column_name: New colum name :param schema: Optional name of schema to use. """

    activity_table = get_activity_table(schema=schema)
    query = (
        activity_table
        .update()
        .values(
            old_data=jsonb_change_key_name(
                activity_table.c.old_data,
                old_column_name,
                new_column_name
            ),
            changed_data=jsonb_change_key_name(
                activity_table.c.changed_data,
                old_column_name,
                new_column_name
            )
        )
        .where(activity_table.c.table_name == table)
    )
    return conn.execute(query)