code: def eval_expr(expr):
      """
      >>> eval_expr('2*6')
      12
      >>> eval_expr('2**6')
      64
      >>> eval_expr('1 + 2*3**(4) / (6 + -7)')
      -161.0
      """
      try:
          return eval_(ast.parse(expr, mode="eval").body)
      except (TypeError, SyntaxError, KeyError) as e:
          raise ValueError(
              f"{expr!r} is not a valid or supported arithmetic expression."
          ) from e
  
imports: import ast
  from dataclasses import dataclass
  import operator
label_desc: Use image node_id 1 for calling a global function with example usage: eval_expr(expr) and returns: eval_