day,month,year,lat,long
01,04,2001,45.00,120.00
02,04,2003,44.00,118.00

import csv
with open("source","rb") as source:
    rdr= csv.reader( source )
    with open("result","wb") as result:
        wtr= csv.writer( result )
        for r in rdr:
            wtr.writerow( (r[0], r[1], r[3], r[4]) )

in_iter= ( (r[0], r[1], r[3], r[4]) for r in rdr )
        wtr.writerows( in_iter )

del r[2]
            wtr.writerow( r )

import pandas as pd
f=pd.read_csv("test.csv")
keep_col = ['day','month','lat','long']
new_f = f[keep_col]
new_f.to_csv("newFile.csv", index=False)

>>>f=pd.read_csv("test.csv")
>>> f
   day  month  year  lat  long
0    1      4  2001   45   120
1    2      4  2003   44   118
>>> keep_col = ['day','month','lat','long']
>>> f[keep_col]
    day  month  lat  long
0    1      4   45   120
1    2      4   44   118
>>>

import csv
ct = 0
cols_i_want = {'cost' : -1, 'date' : -1}
with open("file1.csv","rb") as source:
    rdr = csv.reader( source )
    with open("result","wb") as result:
        wtr = csv.writer( result )
        for row in rdr:
            if ct == 0:
              cc = 0
              for col in row:
                for ciw in cols_i_want:
                  if col == ciw:
                    cols_i_want[ciw] = cc
                cc += 1
            wtr.writerow( (row[cols_i_want['cost']], row[cols_i_want['date']]) )
            ct += 1

import csv

file_name = 'C:Tempmy_file.csv'
output_file = 'C:Tempnew_file.csv'
csv_file = open(file_name, 'r')
## note that the index of the year column is excluded
column_indices = [0,1,3,4]
with open(output_file, 'w') as fh:
    reader = csv.reader(csv_file, delimiter=',')
    for row in reader:
       tmp_row = []
       for col_inx in column_indices:
           tmp_row.append(row[col_inx])
       fh.write(','.join(tmp_row))

outFile = open( 'newFile', 'w' )
for line in open( 'oldFile' ):
   items = line.split( ',' )
   outFile.write( ','.join( items[:2] + items[ 3: ] ) )
outFile.close()

del variable_name['year']

input = [ {'day':01, 'month':04, 'year':2001, ...}, ... ]
for E in input: del E['year']

input = [ [01, 04, 2001, ...],
          [...],
          ...
        ]
for E in input: del E[2]

result= data.drop('year', 1)
result.head(5)