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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 has(self, block, name):
 """ Return whether or not the field named `name` has a non-default value for the XBlock `block`. :param block: block to check :type block: :class:`~xblock.core.XBlock` :param name: field name :type name: str """

        try:
            self.get(block, name)
            return True
        except KeyError:
            return False