def __init__(self, step_addr, action, modifiers=None, name=None,<EOL>description=None):
self.step_addr = step_addr<EOL>self.action = action<EOL>self.modifiers = modifiers or []<EOL>self.name = name or action.__class__.__name__<EOL>self.description = description<EOL>
Initialize a ``Step`` instance.

:param step_addr: The address of the step in the test
                  configuration.
:param action: An ``Action`` instance.
:param modifiers: A list of ``Modifier`` instances, in the
                  order in which processing should be
                  performed.  Optional.
:param name: A name for the step.  Optional.
:param description: A description of the step.  Optional.