How to convert string representation of list in pandas series to a numpy array?

You can use literal_eval() and tolist() as below:

import pandas as pd 
import ast
import numpy as np

inputs = pd.Series(['[11, 21, 8]', '[18, 65, 108]'])
converted_inputs=np.array([ast.literal_eval(row) for row in inputs.tolist()])
print("converted_inputs=\n",converted_inputs)

The output is:

converted_inputs=
 [[ 11  21   8]
 [ 18  65 108]]