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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 locate(self, store=current_store):
 """Gets the URL of the image from the ``store``. :param store: the storage which contains the image. :data:`~sqlalchemy_imageattach.context.current_store` by default :type store: :class:`~sqlalchemy_imageattach.store.Store` :returns: the url of the image :rtype: :class:`str` """

        if not isinstance(store, Store):
            raise TypeError('store must be an instance of '
                            'sqlalchemy_imageattach.store.Store, not ' +
                            repr(store))
        return store.locate(self)