python spread operator

1arr = [3, 4, 5]
2extended_arr = [1, 2, *arr]

1#df = df[['gene_symbol', 'sample_id', 'fc']]
2df = df.pivot(index='gene_symbol',columns='sample_id',values='fc')
3print (df)
4sample_id       S1     S2
5gene_symbol              
6a            100.0    1.3
7b            100.0   14.0
8c            112.0  125.0
9