Connect receiver to signal events sent by sender.
receiver – A callable. Will be invoked by send() with
sender= as a single positional argument and any **kwargs that
were provided to a call to send().
sender – Any object or ANY, defaults to ANY.
Restricts notifications delivered to receiver to only those
send() emissions sent by sender. If ANY, the receiver
will always be notified. A receiver may be connected to
multiple sender values on the same Signal through multiple calls
weak – If true, the Signal will hold a weakref to receiver
and automatically disconnect when receiver goes out of scope or
is garbage collected. Defaults to True.
Emit this signal on behalf of sender, passing on **kwargs.
Returns a list of 2-tuples, pairing receivers with their return
value. The ordering of receiver notification is undefined.
*sender – Any object or None. If omitted, synonymous
with None. Only accepts one positional argument.
**kwargs – Data to be sent to receivers.
Return the NamedSignal name, creating it if required.
Repeated calls to this function will return the same signal object.