def findLeftBrace(self, block, column):
        """Search for a corresponding '{' and return its indentation
        If not found return None
        """
        block, column = self.findBracketBackward(block, column, '{')  # raise ValueError if not found

        try:
            block, column = self.tryParenthesisBeforeBrace(block, column)
        except ValueError:
            pass # leave previous values
        return self._blockIndent(block)
Search for a corresponding '{' and return its indentation
        If not found return None