title: I have no idea why I am getting "can only concatenate str (not "int") to str" ERROR here
body: <p>Code:</p>
  <pre><code>import pandas as pd
  app = pd.read_excel(&quot;/Users/michaelblack/Downloads/Applicants with Interest/Applicants with Interests 2020.xlsx&quot;)
  app = app.replace(',',' ', regex=True).replace('/','', regex=True).replace('-','',regex=True).replace(';',' ',regex=True)
  pd.set_option('display.max_columns', None)
  pd.set_option('display.max_colwidth', None)
  app.fillna(' ', inplace = True)
  app.info()
  ct = 0
  while ct &lt;= 9:
      if ct == 0:
          app['new'+str(ct)] = app['Interest Description'] + ' ' + app['Interest Role']
      else:
          app['new'+str(ct)] = app['Interest Description' + '.' + str(ct)] + ' '+ app['Interest Role' + '.' + str(ct)]
      ct += 1
  
  app.head(5)
  </code></pre>
  <p><em>My error is on line 12 (right above ct += 1) and it is a &quot;can only concatenate str (not &quot;int&quot;) to str&quot;.</em></p>
  <p>For context: every single field in my Excel file is an &quot;object&quot; data type, and I have two other Excel files with the exact same # of columns, column headers, and data types, but just different values, and they both work.</p>
  <p>Can anyone please offer some guidance here?  For the life of me, I am lost.  I can't understand why one identical Excel file would work but another wouldn't, when the code is the EXACT same.</p>