Best way to use Python to make 2d XY scatter graphs? Will TKinter do it?

[rhmd]

I need to create image files (eg bmp or jpeg) of xy scatter graphs
(i.e., graphs in which markers denote individual points; the markers
need to be small polygons of various sizes, shapes, colors, shadings,
etc. and there are thousands on them on each graph).  Have been using
MS Excel, but its limitations are unbelievable (only whole number
sizes, no way around a 56 color palette, only low quality jpeg files
so that when I publish the graphs I have to print and scan them all to
get a decent image, no more than 32K markers in a single series). 
>From a programming point of view, Python is perfect to set up
something like this, but MY QUESTION IS: Will TKinter do this?  Or
will it be necessary to learn OpenGL?  Or is another Python compatible
package best?  Thanks for your help.