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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 resolve(self, ref, document=None):
 """Resolve a ref within the schema. This is just a convenience method, since RefResolver returns both a URI and the resolved value, and we usually just need the resolved value. :param str ref: URI to resolve. :param dict document: Optional schema in which to resolve the URI. :returns: the portion of the schema that the URI references. :see: :meth:`SchemaRefResolver.resolve` """

        _, resolved = self.resolver.resolve(ref, document=document)
        return resolved