code: def cos_3() -> Expr:
      r"""Computes $\cos \frac{\pi}{3}$ in square roots"""
      return S.Half
  
file_path: sympy/sympy/functions/elementary/_trigonometric_special.py
imports: from __future__ import annotations
  from typing import Callable
  from functools import reduce
  from sympy.core.expr import Expr
  from sympy.core.singleton import S
  from sympy.core.intfunc import igcdex
  from sympy.core.numbers import Integer
  from sympy.functions.elementary.miscellaneous import sqrt
  from sympy.core.cache import cacheit
label_desc: Use image node_id 4 for calling a global function with example usage: cos_3() and returns: S