'Set the axisline style.
*axisline_style* can be a string with axisline style name with optional
comma-separated attributes. Alternatively, the attrs can
be provided as keywords.
set_arrowstyle("->,size=1.5")
set_arrowstyle("->", size=1.5)
Old attrs simply are forgotten.
Without argument (or with arrowstyle=None), return
available styles as a list of strings.'

def set_axisline_style(self, axisline_style=None, **kw):

    if (axisline_style == None):
        return AxislineStyle.pprint_styles()
    if isinstance(axisline_style, AxislineStyle._Base):
        self._axisline_style = axisline_style
    else:
        self._axisline_style = AxislineStyle(axisline_style, **kw)
    self._init_line()
