import ast
input = "[[1,2,3],['c',4,'r']]"
output = ast.literal_eval(input)
output
=> [[1, 2, 3], ['c', 4, 'r']]
# Extract list from a str
import ast
input = "[[1,2,3],['c',4,'r']]"
output = ast.literal_eval(input)
output
=> [[1, 2, 3], ['c', 4, 'r']]