plot legends

Hi,

  This evening i played a bit with trying to add
a legend to a plot widget that i have.
Here is the relevant test code snippet
(based on the example: embedding_in_wx.py)

class PlotFigure(wxFrame):

    def plotMultiYData(self, xList, yLists, xRangeList, yRangeList):

        a = self.figmgr.add_subplot(111)
        
        x = self.__listToFloatArray(xList)

        for yList in yLists:

            y = self.__listToFloatArray(yList)

            a.plot(x,y, marker='o', markersize=4.0)
            a.legend(('aLabel'), 'upper center')

            a.set_xlim(xRangeList)
            a.set_ylim(yRangeList)

        # End of: for yList in yLists:
        
        self.toolbar.update()

The aLabel gets printed like:
     a
     L
     a
     b
     e
     l

and the first plot associates with the first 'a'
the second with the 'L' etc. Clearly at the moment
i'm only trying to apply a legend to the first plot.
Once i get that sorted out i would expect
('legend1', legend2') to work for 2 plots etc.

Anyone want to give me a hint as to what i'm doing wrong here?

I would really like to specify that the legend appear
off of the plot...say to the left of the y axis tick
marks...any hints here?

Thanks,

Jim