title: gspread update_cell very slow
body: <p>I have two google spreadsheets:</p>
  
  <p>QC- many columns, I want to check if a value from column 4 appears in the second spreadsheet lastEdited_PEID; if it does, it would put 'Bingo!' in column 14 of the same row where the value was found</p>
  
  <p>lastEdited- one column, long spreadsheets of values</p>
  
  <p>I achieve that with the following code:</p>
  
  <pre><code>#acces the documents on Drive
  QC = gc.open_by_key("FIRST KEY").sheet1
  lastEdited = gc.open_by_key("SECOND KEY").sheet1
  
  #get values from columns and convert to lists 
  QC_PEID = QC.col_values(4)
  lastEdited_PEID = lastEdited.col_values(1)
  
  #iterate by rows and check if value from each row appears in the second document
  for value in QC_PEID:
      ind = QC_PEID.index(value)
      if value in lastEdited_PEID:
          QC.update_cell(ind, 14, 'Bingo!')
  </code></pre>
  
  <p>So it does the job but does it very slowly (about 5 minutes). I am concerned about the speed because I have to perform the operation for about 50 spreadsheets (avg. 6000 rows each).</p>
  
  <p>I tried to remove the element from the second list when found (it can only appear once) with the following code in the loop:</p>
  
  <pre><code>    for value in QC_PEID:
          ind = QC_PEID.index(value)
          if value in lastEdited_PEID:
              QC.update_cell(ind, 14, 'Bingo!')
              **lastEdited_PEID.remove('value')**
  </code></pre>
  
  <p>I thought it would make it faster as the reference list would be shorter but surprisingly it takes even more.</p>
  
  <p>What could I do to make the process quicker?</p>