title: openpyxl: assign value or apply format to a range of Excel cells without iteration
body: <p>I would like to apply a specific format or assign a value to a range of Excel cells without iterating over each cell. I am currently using this script:</p>
  
  <pre><code>from openpyxl import Workbook
  from openpyxl.styles import Font
  wb = Workbook()
  ws = wb.active
  
  ## With iterations
  
  # Apply style
  for i, rowOfCellObjects in enumerate(ws['A1':'C4']):
      for n, cellObj in enumerate(rowOfCellObjects):
          cellObj.fill = Font(name='Times New Roman')
  
  # Assign singular value to all cells
  for i, rowOfCellObjects in enumerate(ws['A1':'C4']):
      for n, cellObj in enumerate(rowOfCellObjects):
          cellObj.value = 3
  
  wb.save("test.xlsx")
  </code></pre>
  
  <p>But I am looking for a shorter notation, like this:</p>
  
  <pre><code>from openpyxl import Workbook
  from openpyxl.styles import Font
  wb = Workbook()
  ws = wb.active
  
  ## Without iterations
  
  # Apply style
  ws['A1':'C4'].fill = Font(name='Times New Roman')
  
  # Assign singular value to all cells
  ws['A1':'C4'].value = 3
  
  wb.save("test.xlsx")
  </code></pre>
  
  <p>Does <code>openpyxl</code> or another module offers something like this?</p>
  
  <p><em>ps: I'm using Python 3.5</em></p>