The ``pyhello.py`` example was initally directly copied from the archive
``ivycpy-0.2`` (the Ivy python version built on top of the C library using
SWIG) available on the official Ivy project's downloads page.

Two differences from the original:

- the initial import statement was::

    from ivycpy import *

  while this version uses::

    from ivy.std_api import *

- ivycpy does not supply to the callbacks the reference to the agent
  triggering an event; ivy-python v1.x has the same behaviour.

  However, since v2.0, every callback triggered by ivy-python gets an
``ivy.IvyClient`` as its first parameter.
