proper syntax for itertuples?

[ilcaa72]

i have this code the keeps giving me errors. i cant seem to get the correct syntax, can anyone assist? below is the dataframe and error is: TypeError: tuple indices must be integers or slices, not str

for i in df.itertuples():
  if i['Close'] > i['prev']:
    i['trade2'] = '+'
    x = '+'
    continue
  elif i['Close'] < i['prev']:
    i['trade2'] = '-'
    x = '-'
    continue
  elif i['Close'] == i['prev']:
    i['trade2'] = x