[Python] Pure polars version of safe ast literal eval

I have data like this,

df = pl.DataFrame({'a': ["['b', 'c', 'd']"]})


I want to convert the string to a list I use,

df = df.with_columns(a=pl.col('a').str.json_decode())


it gives me,

ComputeError: error inferring JSON: InternalError(TapeError) at character 1 (''')


then I use this function,

import ast
def safe_literal_eval(val):
try:
return ast.literal_eval(val)
except (ValueError, SyntaxError):
return val
df = df.with_columns(a=pl.col('a').map_elements(safe_literal_eval, return_dtype=pl.List(pl.String)))


and get the expected output, but is there a pure polars way to achieve the same?

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