title: AttributeError: 'DataFrame' object has no attribute 'rt'
body: <p>I keep getting this error even though the attribute 'rt' is there in my dataframe. It was working before and I am not sure why it's not working now. Any ideas?</p>
  <p>This is how my code looks:</p>
  <pre><code>path1 = '/home/data/1-23.csv'
  file1 = pd.read_csv(path1,skipinitialspace=True, index_col=None)
  df1 = file1[~file1.rt.isna()]
  df1 = file1[~file1.comment2.isna()]
  
  df1 = df1[['word','value','color','rt']]
  print(df1.head())
  </code></pre>
  <p>This is how the data looks:</p>
  <pre><code>resultstime,ipaddress,controller,numberitem,innernumber,label,latingp,penntype,pennname,parameter,value,eventime,word,color,correct,rt,comment2                                                             
  1619906522,529a13d061460b9dd2ecdcd4dcd0b118,PennController,43,0,experimental-trial,NULL,PennController,44,_Trial_,Start,1619906424186,CHOQUE, green, v,1353,NULL                                                                
  1619906522,529a13d061460b9dd2ecdcd4dcd0b118,PennController,43,0,experimental-trial,NULL,Text,word,Print,NA,1619906424186,CHOQUE, green, v,1353,NULL                                                             
  1619906522,529a13d061460b9dd2ecdcd4dcd0b118,PennController,43,0,experimental-trial,NULL,Key,keypress,PressedKey,V,1619906425542,CHOQUE, green, v,1353,Wait success                                                              
  </code></pre>