Function literal_eval

Lib/ast.py:51–64

Evaluate an expression node or a string containing only a Python expression. The string or node provided may only consist of the following Python literal structures: strings, bytes, numbers, tuples, lists, dicts, sets, booleans, and None. Caution: A complex expression can over

(node_or_string)

def literal_eval(node_or_string):
    """
    Evaluate an expression node or a string containing only a Python
    expression.  The string or node provided may only consist of the following
    Python literal structures: strings, bytes, numbers, tuples, lists, dicts,
    sets, booleans, and None.

    Caution: A complex expression can overflow the C stack and cause a crash.
    """
    if isinstance(node_or_string, str):
        node_or_string = parse(node_or_string.lstrip(" \t"), mode='eval').body
    elif isinstance(node_or_string, Expression):
        node_or_string = node_or_string.body
    return _convert_literal(node_or_string)


def _convert_literal(node):