'Set the label for an axis. Basic HTML formatting is allowed.
**Arguments:**
axis            must be one of \'left\', \'bottom\', \'right\', or \'top\'
text            text to display along the axis. HTML allowed.
units           units to display after the title. If units are given,
then an SI prefix will be automatically appended
and the axis values will be scaled accordingly.
(ie, use \'V\' instead of \'mV\'; \'m\' will be added automatically)'

def setLabel(self, axis, text=None, units=None, unitPrefix=None, **args):

    self.getAxis(axis).setLabel(text=text, units=units, **args)
    self.showAxis(axis)
