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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 register(self, alias, uri):
 """ Register a new schema URI under a given name. """

        # TODO: do we want to constrain the valid alias names.
        if isinstance(uri, dict):
            id = uri.get('id', alias)
            self.resolver.store[id] = uri
            uri = id
        self.aliases[alias] = uri