title: openpyxl - adding new rows in excel file with merged cell existing
body: <p><a href="https://i.stack.imgur.com/20JFY.png" rel="noreferrer">Before</a></p>
  
  <p><a href="https://i.stack.imgur.com/9d7m6.png" rel="noreferrer">After</a></p>
  
  <p>So, I was trying to add 6 rows into the excelsheet.
  And I used 
  openpyxl.worksheet.worksheet.Worksheet.insert_rows(ws,idx=0,amount=6) 
  to help me accomplish the task. 
  This line works perfect with normal excel file. </p>
  
  <p>But, when it comes to the excel file contained merged cells. The program will  not working properly just like the image I attached. </p>
  
  <p>Could someone give me some ideas about how to solve the issue. I ran out all the ideas and need some inspirations.</p>
  
  <p>Thank you very much for whoever answers my questions!!</p>