[Python] Splitting a pandas dataframe column by delimiter

i have a small sample data:

import pandas as pd

df = {'ID': [3009, 129, 119, 120, 121, 122, 130, 3014, 266, 849, 174, 844],
'V': ['IGHV7-B*01', 'IGHV7-B*01', 'IGHV6-A*01', 'GHV6-A*01', 'IGHV6-A*01',
'IGHV6-A*01', 'IGHV4-L*03', 'IGHV4-L*03', 'IGHV5-A*01', 'IGHV5-A*04',
'IGHV6-A*02','IGHV6-A*02'],
'Prob': [1, 1, 0.8, 0.8056, 0.9, 0.805, 1, 1, 0.997, 0.401, 1, 1]}

df = pd.DataFrame(df)


looks like

df

Out[25]:
ID Prob V
0 3009 1.0000 IGHV7-B*01
1 129 1.0000 IGHV7-B*01
2 119 0.8000 IGHV6-A*01
3 120 0.8056 IGHV6-A*01
4 121 0.9000 IGHV6-A*01
5 122 0.8050 IGHV6-A*01
6 130 1.0000 IGHV4-L*03
7 3014 1.0000 IGHV4-L*03
8 266 0.9970 IGHV5-A*01
9 849 0.4010 IGHV5-A*04
10 174 1.0000 IGHV6-A*02
11 844 1.0000 IGHV6-A*02


I want to split the column 'V' by the '-' delimiter and move it to another column named 'allele'

Out[25]:
ID Prob V allele
0 3009 1.0000 IGHV7 B*01
1 129 1.0000 IGHV7 B*01
2 119 0.8000 IGHV6 A*01
3 120 0.8056 IGHV6 A*01
4 121 0.9000 IGHV6 A*01
5 122 0.8050 IGHV6 A*01
6 130 1.0000 IGHV4 L*03
7 3014 1.0000 IGHV4 L*03
8 266 0.9970 IGHV5 A*01
9 849 0.4010 IGHV5 A*04
10 174 1.0000 IGHV6 A*02
11 844 1.0000 IGHV6 A*02


the code i have tried so far is incomplete and didn't work:

df1 = pd.DataFrame()
df1[['V']] = pd.DataFrame([ x.split('-') for x in df['V'].tolist() ])


or

df.add(Series, axis='columns', level = None, fill_value = None)
newdata = df.DataFrame({'V':df['V'].iloc[::2].values,
'Allele': df['V'].iloc[1::2].values})

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