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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 connect(self, f, mode=None):
 """ Connect an object `f` to the signal. The type the object needs to have depends on `mode`, but usually it needs to be a callable. :meth:`connect` returns an opaque token which can be used with :meth:`disconnect` to disconnect the object from the signal. The default value for `mode` is :attr:`STRONG`. Any decorator can be used as argument for `mode` and it is applied to `f`. The result is stored internally and is what will be called when the signal is being emitted. If the result of `mode` returns a false value during emission, the connection is removed. .. note:: The return values required by the callable returned by `mode` and the one required by a callable passed to `f` using the predefined modes are complementary! A callable `f` needs to return true to be removed from the connections, while a callable returned by the `mode` decorator needs to return false. Existing modes are listed below. """


        mode = mode or self.STRONG
        self.logger.debug("connecting %r with mode %r", f, mode)
        return self._connect(mode(f))