title: Renaming sheets in Excel using Python; referencing cell value for sheet name
body: <p>I have been working on a project using Python to build a program that simplifies changes to be made in Microsoft Excel. I am attempting to loop through a workbook to rename all of the sheets. The main difference my problem has from what I have read is that I am renaming the sheets based on a value in a cell using the following code: </p>
  
  <pre><code>"""Loop through each worksheet and rename the sheet using a value from the sheet."""
  for i in wb:
      ws = wb.active
      c = ws['A1']
      ws.title = c + (i + 1)
      print(sheet.title)
  </code></pre>
  
  <p>If someone could clarify what the issue is I would greatly appreciate your assistance. I received the following error report:</p>
  
  <pre><code>Traceback (most recent call last):
    File "&lt;stdin&gt;", line 4, in &lt;module&gt;
    File "C:\Users\Que\AppData\Local\Programs\Python\Python37-32\lib\site-packages\openpyxl\workbook\child.py", line 93, in title
      m = INVALID_TITLE_REGEX.search(value)
  TypeError: expected string or bytes-like object
  </code></pre>
  
  <p>I am using Powershell interactive mode to test each piece of code. Please understand I am attempting to access a value in a cell and have made several attempts to change the code to reflect my objective. Your insight and observations are appreciated.</p>