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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 initialize(self, session=None, force=False):
 """ Initializes TensorFlow variables, which are returned by `initializables` property and uses feed dictionary returned by `initializable_feeds` property defined at ICompilable interface and implemented by descendants. :param session: TensorFlow session used for initializing. In case when session is None, default TensorFlow session will be checked first, if session is still None, then default GPflowFlow session will used, but there is *no garuantee* that GPflow session's graph is compliant with node's tensors graph. :param force: inidicates either the initialized TensorFlow variables must be re-initialized or not. :raises: GPflowError exception if session's graph is different from the graph used by node tensors. """

        session = self.enquire_session(session)
        initializables = self.initializables
        if initializables:
            misc.initialize_variables(
                variables=initializables,
                session=session,
                force=force,
                feed_dict=self.initializable_feeds)