I am trying to add two columns and create a new one. This new column should become the first column in the dataframe or the output csv file. 

```
column_1 column_2
84       test
65       test

```

Output should be 

```
column         column_1 column_2
trial_84_test   84      test
trial_65_test   65      test

```

I tried below given methods but they did not work:

```
sum = str(data['column_1']) + data['column_2']

data['column']=data.apply(lambda x:'%s_%s_%s' % ('trial' + data['column_1'] + data['column_2']),axis=1)

```

Help is surely appreciated.