BigInt type for format: int64 types in swagger

Can I make (maybe using --custom or --templates) with this generator types BigInt for and only for
```
type: integer
format: int64
```
?
For example i have structure
```
pet:
type: object
properties:
age:
type: integer
unique_big_id:
type: integer
format: int64
```
Can i get generated type
```
export interface Pet {
age: number;
unique_big_id: BigInt;
}
```
and marshal response from response from server `{ "unique_big_id" : 9223372036854775807, "age": 123 }` to Pet without losing precision to 9223372036854775000?