code: func (f *FlagSet) Bool(name string, value bool, usage string) *bool {
  	p := new(bool)
  	f.BoolVar(p, name, value, usage)
  	return p
  }
docs: // Bool defines a bool flag with specified name, default value, and usage string.
  // The return value is the address of a bool variable that stores the value of the flag.