code: func GetInt64PtrEmptyZero(d *schema.ResourceData, key string) *int64 {
  	i := GetInt64Ptr(d, key)
  	if i != nil {
  		return i
  	}
  	return Int64Ptr(int64(0))
  }
docs: // GetInt64PtrEmptyZero reads a ResourceData and returns an appropriate *int64
  // for the state of the definition. 0 is returned if it does not exist.