'clear the current axis'

def cla(self):

    self.set_major_locator(mticker.AutoLocator())
    self.set_major_formatter(mticker.ScalarFormatter())
    self.set_minor_locator(mticker.NullLocator())
    self.set_minor_formatter(mticker.NullFormatter())
    self.set_label_text(u'')
    self._set_artist_props(self.label)
    self.isDefault_majloc = True
    self.isDefault_minloc = True
    self.isDefault_majfmt = True
    self.isDefault_minfmt = True
    self.isDefault_label = True
    self.callbacks = cbook.CallbackRegistry()
    self._gridOnMajor = (rcParams[u'axes.grid'] and (rcParams[u'axes.grid.which'] in (u'both', u'major')))
    self._gridOnMinor = (rcParams[u'axes.grid'] and (rcParams[u'axes.grid.which'] in (u'both', u'minor')))
    self.label.set_text(u'')
    self._set_artist_props(self.label)
    self.reset_ticks()
    self.converter = None
    self.units = None
    self.set_units(None)
    self.stale = True
