def _compute_used_globals(cls, func, table, co_consts, co_names):
        """
        Compute the globals used by the function with the given
        bytecode table.
        """
        d = {}
        globs = func.__globals__
        builtins = globs.get('__builtins__', utils.builtins)
        if isinstance(builtins, ModuleType):
            builtins = builtins.__dict__
        # Look for LOAD_GLOBALs in the bytecode
        for inst in table.values():
            if inst.opname == 'LOAD_GLOBAL':
                name = co_names[_fix_LOAD_GLOBAL_arg(inst.arg)]
                if name not in d:
                    try:
                        value = globs[name]
                    except KeyError:
                        value = builtins[name]
                    d[name] = value
        # Add globals used by any nested code object
        for co in co_consts:
            if isinstance(co, CodeType):
                subtable = OrderedDict(ByteCodeIter(co))
                d.update(cls._compute_used_globals(func, subtable,
                                                   co.co_consts, co.co_names))
        return d

        Compute the globals used by the function with the given
        bytecode table.
        
numba/core/bytecode.py