## Types

```typescript
type Currency = "Unknown" | "Usd" | "EQ" | "Eth" | "Btc" | "Eos" | "Dot";
type UserGroup = "Unknown" | "Balances" | "Bailsman";
type UnsubscribePromise = Promise<() => void /* call this func to unsubscribe */>;

interface SignedBalance {
  readonly isPositive: boolean;
  readonly asPositive: Balance;
  readonly isNegative: boolean;
  readonly asNegative: Balance;
}

interface DataPoint {
  price: u64;
  account_id: AccountId;
  block_number: BlockNumber;
  timestamp: u64;
}

interface PricePoint {
  block_number: BlockNumber;
  timestamp: u64;
  price: u64;
  data_points: Vec<DataPoint>;
}
```