def many_to_one(clsname, **kw):
@declared_attr<EOL>def m2o(cls):<EOL><INDENT>cls._references((cls.__name__, clsname))<EOL>return relationship(clsname, **kw)<EOL><DEDENT>return m2o<EOL>
Use an event to build a many-to-one relationship on a class.

    This makes use of the :meth:`.References._reference_table` method
    to generate a full foreign key relationship to the remote table.