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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 populate_context(self, context, environ):
 """Set initial context values."""

        url = self.get_url(environ)
        context['base_url'] = url
        transaction_id = uuid.uuid4().hex
        context['transaction_id'] = transaction_id
        LOG.debug("Context created: base_url=%s, tid=%s", url, transaction_id)