docs: def line_number_area_width(self):
          """
          Computes the lineNumber area width depending on the number of lines
          in the document
  
          :return: Widtg
          """
          digits = 1
          count = max(1, self.editor.blockCount())
          while count >= 10:
              count /= 10
              digits += 1
          space = 5 + self.editor.fontMetrics().width("9") * digits
          return space