Following up on https://github.com/SimpleITK/SlicerSimpleFilters/pull/10/, I wonder if it would be helpful to have a mixin similar to slicer.util.VTKObservationMixin but for Qt connection (may be QConnectionMixin).

Then to establish a connection, you would do:

self.connect(object, signal, callback)

with connect method being provided by the mixin.

In the context of the referenced PR, the class would be declared like this:

class FilterParameters(object, QConnectionMixin):
  def __init__(self, parent=None):
    [...]
    QConnectionMixin.__init__(self)

  def __del__(self):
    self.removeConnections()
    [...]

  def create(self):
    [...]
    self.connect(fiducialSelector, "nodeActivated(vtkMRMLNode*)", lambda node,name=name:self.onFiducialListNode(name,node))