def maybe_increment_lambda_arguments(self, leaf: Leaf) -> bool:
        """In a lambda expression, there might be more than one argument.

        To avoid splitting on the comma in this situation, increase the depth of
        tokens between `lambda` and `:`.
        """
        if leaf.type == token.NAME and leaf.value == "lambda":
            self.depth += 1
            self._lambda_argument_depths.append(self.depth)
            return True

        return False
In a lambda expression, there might be more than one argument.

        To avoid splitting on the comma in this situation, increase the depth of
        tokens between `lambda` and `:`.
        
src/black/brackets.py