How to split at specified delimiter

[snippsat]

but it does not print give any output.

He do it from interactive shell.
Like this without:

import re

regex = re.compile(r"\d*E\d*")
match = regex.search('VN009K30E6T00')
aa = match.group()
print(aa)

I have below DataFrame:

When using pandas,you should not take it out of DataFrame and use regex.
pandas has build in regex(str) to deal with DataFrame.
Example:

import pandas as pd

df = pd.DataFrame(
    [['VA004L200E2T99',77, 999],
     ['VG002K500E4T99',55, 100],
     ['VN009K30E6T00',33, 9]],
     columns=['val','foo', 'bar']
)

df['val'] = df['val'].str.extract(r'(\d*E\d*)', expand=False)
print(df)

Output:
     val  foo  bar
0  200E2   77  999
1  500E4   55  100
2   30E6   33    9