human
I wrote the below code

    def _(f):
        destination = (src - 1)
        @do(op.setitem(_downgrade_methods, destination))
        @wraps(f)
        def wrapper(op, conn, version_info_table):
            conn.execute(version_info_table.delete())
            f(op)
            write_version_info(conn, version_info_table, destination)
        return wrapper
    return _

What's a good function header?
assistant
#Here's a good function header.

def downgrades(src):