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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 dynamic_start(self, access_token, instance_url=None, **kw):
 """ Set the access token dynamically according to the current user. More parameters can be set. """

        self.dynamic = {'access_token': str(access_token), 'instance_url': str(instance_url)}
        self.dynamic.update(kw)