rng=pd.date_range('1/1/2012',periods=100,freq='S')

ts=pd.Series(np.random.randint(0,500,len(rng)),index=rng)

rng

DatetimeIndex(['2012-01-01 00:00:00', '2012-01-01 00:00:01',
'2012-01-01 00:00:02', '2012-01-01 00:00:03',
'2012-01-01 00:00:04', '2012-01-01 00:00:05',
'2012-01-01 00:00:06', '2012-01-01 00:00:07',
'2012-01-01 00:00:08', '2012-01-01 00:00:09',
'2012-01-01 00:00:10', '2012-01-01 00:00:11',
'2012-01-01 00:00:12', '2012-01-01 00:00:13',
'2012-01-01 00:00:14', '2012-01-01 00:00:15',
'2012-01-01 00:00:16', '2012-01-01 00:00:17',
'2012-01-01 00:00:18', '2012-01-01 00:00:19',
'2012-01-01 00:00:20', '2012-01-01 00:00:21',
'2012-01-01 00:00:22', '2012-01-01 00:00:23',
'2012-01-01 00:00:24', '2012-01-01 00:00:25',
'2012-01-01 00:00:26', '2012-01-01 00:00:27',
'2012-01-01 00:00:28', '2012-01-01 00:00:29',
'2012-01-01 00:00:30', '2012-01-01 00:00:31',
'2012-01-01 00:00:32', '2012-01-01 00:00:33',
'2012-01-01 00:00:34', '2012-01-01 00:00:35',
'2012-01-01 00:00:36', '2012-01-01 00:00:37',
'2012-01-01 00:00:38', '2012-01-01 00:00:39',
'2012-01-01 00:00:40', '2012-01-01 00:00:41',
'2012-01-01 00:00:42', '2012-01-01 00:00:43',
'2012-01-01 00:00:44', '2012-01-01 00:00:45',
'2012-01-01 00:00:46', '2012-01-01 00:00:47',
'2012-01-01 00:00:48', '2012-01-01 00:00:49',
'2012-01-01 00:00:50', '2012-01-01 00:00:51',
'2012-01-01 00:00:52', '2012-01-01 00:00:53',
'2012-01-01 00:00:54', '2012-01-01 00:00:55',
'2012-01-01 00:00:56', '2012-01-01 00:00:57',
'2012-01-01 00:00:58', '2012-01-01 00:00:59',
'2012-01-01 00:01:00', '2012-01-01 00:01:01',
'2012-01-01 00:01:02', '2012-01-01 00:01:03',
'2012-01-01 00:01:04', '2012-01-01 00:01:05',
'2012-01-01 00:01:06', '2012-01-01 00:01:07',
'2012-01-01 00:01:08', '2012-01-01 00:01:09',
'2012-01-01 00:01:10', '2012-01-01 00:01:11',
'2012-01-01 00:01:12', '2012-01-01 00:01:13',
'2012-01-01 00:01:14', '2012-01-01 00:01:15',
'2012-01-01 00:01:16', '2012-01-01 00:01:17',
'2012-01-01 00:01:18', '2012-01-01 00:01:19',
'2012-01-01 00:01:20', '2012-01-01 00:01:21',
'2012-01-01 00:01:22', '2012-01-01 00:01:23',
'2012-01-01 00:01:24', '2012-01-01 00:01:25',
'2012-01-01 00:01:26', '2012-01-01 00:01:27',
'2012-01-01 00:01:28', '2012-01-01 00:01:29',
'2012-01-01 00:01:30', '2012-01-01 00:01:31',
'2012-01-01 00:01:32', '2012-01-01 00:01:33',
'2012-01-01 00:01:34', '2012-01-01 00:01:35',
'2012-01-01 00:01:36', '2012-01-01 00:01:37',
'2012-01-01 00:01:38', '2012-01-01 00:01:39'],
dtype='datetime64[ns]', freq='S')

ts

2012-01-01 00:00:00 64
2012-01-01 00:00:01 242
2012-01-01 00:00:02 82
2012-01-01 00:00:03 57
2012-01-01 00:00:04 285
2012-01-01 00:00:05 200
2012-01-01 00:00:06 112
2012-01-01 00:00:07 353
2012-01-01 00:00:08 405
2012-01-01 00:00:09 245
2012-01-01 00:00:10 297
2012-01-01 00:00:11 20
2012-01-01 00:00:12 496
2012-01-01 00:00:13 50
2012-01-01 00:00:14 127
2012-01-01 00:00:15 323
2012-01-01 00:00:16 119
2012-01-01 00:00:17 429
2012-01-01 00:00:18 41
2012-01-01 00:00:19 18
2012-01-01 00:00:20 285
2012-01-01 00:00:21 32
2012-01-01 00:00:22 445
2012-01-01 00:00:23 127
2012-01-01 00:00:24 81
2012-01-01 00:00:25 84
2012-01-01 00:00:26 108
2012-01-01 00:00:27 476
2012-01-01 00:00:28 214
2012-01-01 00:00:29 92
...
2012-01-01 00:01:10 193
2012-01-01 00:01:11 297
2012-01-01 00:01:12 17
2012-01-01 00:01:13 347
2012-01-01 00:01:14 95
2012-01-01 00:01:15 166
2012-01-01 00:01:16 136
2012-01-01 00:01:17 366
2012-01-01 00:01:18 72
2012-01-01 00:01:19 441
2012-01-01 00:01:20 354
2012-01-01 00:01:21 15
2012-01-01 00:01:22 379
2012-01-01 00:01:23 86
2012-01-01 00:01:24 452
2012-01-01 00:01:25 205
2012-01-01 00:01:26 165
2012-01-01 00:01:27 172
2012-01-01 00:01:28 50
2012-01-01 00:01:29 409
2012-01-01 00:01:30 27
2012-01-01 00:01:31 330
2012-01-01 00:01:32 46
2012-01-01 00:01:33 173
2012-01-01 00:01:34 274
2012-01-01 00:01:35 345
2012-01-01 00:01:36 205
2012-01-01 00:01:37 332
2012-01-01 00:01:38 462
2012-01-01 00:01:39 150
Freq: S, Length: 100, dtype: int32

ts.resample('5Min').sum()

2012-01-01 23081
Freq: 5T, dtype: int32