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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 _check_lambda_alias(self):
 """Check if lambda alias exists. Returns: True if alias exists False if alias does not exist """

        aliases = self.lambda_client.list_aliases(FunctionName=self.app_name)

        matched_alias = False
        for alias in aliases['Aliases']:
            if alias['Name'] == self.env:
                LOG.info('Found alias %s for function %s', self.env, self.app_name)
                matched_alias = True
                break
        else:
            LOG.info('No alias %s found for function %s', self.env, self.app_name)
        return matched_alias