Call unspecified API

```
public interface Call<T extends Object>

                    
```
A pending operation waiting to be ran.
There are several ways to run a Call:
- execute: synchronous, blocking
- enqueue: async, callback based
- await: async, suspending call
Running a Call more than once results in undefined behaviour.

Method Summary

Modifier and Type	Method	Description
`abstract Result<T>`	`execute()`	Executes the call synchronously, in a blocking way.
`abstract Unit`	`enqueue(Function1<Result<T>, Unit> callback)`	Executes the call asynchronously, on a background thread.
`abstract Unit`	`cancel()`	Cancels the execution of the call, if cancellation is supported for the operation.

Methods inherited from class io.getstream.chat.android.client.call.Call
equals, hashCode, toString
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - execute
```
@WorkerThread() abstract Result<T> execute()
```
    Executes the call synchronously, in a blocking way. Only call this from a background thread.
  - enqueue
```
 abstract Unit enqueue(Function1<Result<T>, Unit> callback)
```
    Executes the call asynchronously, on a background thread. Safe to call from the main thread. The callback will always be invoked on the main thread.
  - cancel
```
 abstract Unit cancel()
```
    Cancels the execution of the call, if cancellation is supported for the operation.
    Note that calls can not be cancelled when running them with execute.