Add a date column to csv using python -

i have following code writes data output csv file. want add date variable @ end of each row using yesterday.strftime variable using in creating filename. example:

thanks!

my current output like:

columna

1

2

and want add following column:

date

2/5/2016

2/5/2016

. . .

code::

filepath = 'c:\\test\\'    filename = yesterday.strftime('%y-%m-%d') + '_' + 'test.csv'  f = open( filename, 'wt') writer = csv.writer(f, lineterminator='\n') header = [h['name'][3:] h in results.get('columnheaders')]  writer.writerow(header) print(''.join('%30s' % h h in header))  # write data table. if results.get('rows', []):   row in results.get('rows'):     writer.writerow(row)     print(''.join('%30s' % r r in row))  else:   print ('no rows found')  f.close() 

in [26]: import pandas pd  in [27]: import datetime  in [28]: = pd.read_csv('a.csv')  in [29]: out[29]:  columna 0        1 1        2  in [30]: a['date'] = [datetime.date.today()]*len(a)  in [31]: out[31]:  columna        date 0        1  2016-02-05 1        2  2016-02-05  in [32]: a.to_csv('adate.csv') 

generally: https://www.airpair.com/python/posts/top-mistakes-python-big-data-analytics