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

        exists = False
        try:
            self.lambda_client.get_function(FunctionName=self.app_name)
            exists = True
        except boto3.exceptions.botocore.exceptions.ClientError:
            pass
        return exists