rx/operators/observable/blocking/first.py
def first(source: BlockingObservable) -> Any:
    """
    Blocks until the first element emits from a BlockingObservable.

    If no item is emitted when on_completed() is called, an exception is thrown

    Note: This will block even if the underlying Observable is
    asynchronous.

    Keyword arguments:
    source -- Blocking observable sequence.

    Returns the first item to be emitted from the blocking observable.
    """
    return next(iter(source.to_iterable()))

    Blocks until the first element emits from a BlockingObservable.

    If no item is emitted when on_completed() is called, an exception is thrown

    Note: This will block even if the underlying Observable is
    asynchronous.

    Keyword arguments:
    source -- Blocking observable sequence.

    Returns the first item to be emitted from the blocking observable.
    
Blocks until the first element emits from a BlockingObservable.
If no item is emitted when on_completed() is called, an exception is thrown

This will block even if the underlying Observable is
asynchronous.

Keyword arguments:
source -- Blocking observable sequence.

Returns the first item to be emitted from the blocking observable.
Blocks until the first element emits from a BlockingObservable . If no item is emitted when on_completed () is called an exception is thrown This will block even if the underlying Observable is asynchronous . Keyword arguments : source -- Blocking observable sequence . Returns the first item to be emitted from the blocking observable .
def first(source: BlockingObservable) -> Any:
    return next(iter(source.to_iterable()))
def first ( source : BlockingObservable ) -> Any : return next ( iter ( source . to_iterable ( ) ) )
Blocks until the first element emits from a BlockingObservable.
Blocks until the first element emits from a BlockingObservable .
"""
    Blocks until the first element emits from a BlockingObservable.

    If no item is emitted when on_completed() is called, an exception is thrown

    Note: This will block even if the underlying Observable is
    asynchronous.

    Keyword arguments:
    source -- Blocking observable sequence.

    Returns the first item to be emitted from the blocking observable.
    """
source
BlockingObservable