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type Getter = {  <Value>(atom: Atom<Value | Promise<Value>>): Value  <Value>(atom: Atom<Promise<Value>>): Value  <Value>(atom: Atom<Value>): Awaited<Value>}
type WriteGetter = Getter & {  <Value>(    atom: Atom<Value | Promise<Value>>,    options: { unstable_promise: true }  ): Promise<Value> | Value  <Value>(atom: Atom<Promise<Value>>, options: { unstable_promise: true }):    | Promise<Value>    | Value  <Value>(atom: Atom<Value>, options: { unstable_promise: true }):    | Promise<Awaited<Value>>    | Awaited<Value>}
type Setter = {  <Value, Result extends void | Promise<void>>(    atom: WritableAtom<Value, undefined, Result>  ): Result  <Value, Update, Result extends void | Promise<void>>(    atom: WritableAtom<Value, Update, Result>,    update: Update  ): Result}
type Read<Value> = (get: Getter) => Value
type Write<Update, Result extends void | Promise<void>> = (  get: WriteGetter,  set: Setter,  update: Update) => Result
type WithInitialValue<Value> = {  init: Value}
// Not exported for public API// Are there better typings?export type SetAtom<  Update,  Result extends void | Promise<void>> = undefined extends Update  ? (update?: Update) => Result  : (update: Update) => Result
type OnUnmount = () => voidtype OnMount<Update, Result extends void | Promise<void>> = <  S extends SetAtom<Update, Result>>(  setAtom: S) => OnUnmount | void
export interface Atom<Value> {  toString: () => string  debugLabel?: string  read: Read<Value>}
export interface WritableAtom<  Value,  Update,  Result extends void | Promise<void> = void> extends Atom<Value> {  write: Write<Update, Result>  onMount?: OnMount<Update, Result>}
type SetStateAction<Value> = Value | ((prev: Value) => Value)
export type PrimitiveAtom<Value> = WritableAtom<Value, SetStateAction<Value>>
let keyCount = 0 // global key count for all atoms
// writable derived atomexport function atom<Value, Update, Result extends void | Promise<void> = void>(  read: Read<Value>,  write: Write<Update, Result>): WritableAtom<Value, Update, Result>
// read-only derived atomexport function atom<Value>(read: Read<Value>): Atom<Value>
// invalid function in the first argumentexport function atom(invalidFunction: (...args: any) => any, write?: any): never
// write-only derived atomexport function atom<Value, Update, Result extends void | Promise<void> = void>(  initialValue: Value,  write: Write<Update, Result>): WritableAtom<Value, Update, Result> & WithInitialValue<Value>
// primitive atomexport function atom<Value>(  initialValue: Value): PrimitiveAtom<Value> & WithInitialValue<Value>
export function atom<Value, Update, Result extends void | Promise<void>>(  read: Value | Read<Value>,  write?: Write<Update, Result>) {  const key = `atom${++keyCount}`  const config = {    toString: () => key,  } as WritableAtom<Value, Update, Result> & { init?: Value }  if (typeof read === 'function') {    config.read = read as Read<Value>  } else {    config.init = read    config.read = (get) => get(config)    config.write = (get, set, update) =>      set(config, typeof update === 'function' ? update(get(config)) : update)  }  if (write) {    config.write = write  }  return config}