The surface or canvas established with wx.PaintDC() can be used to draw a number of shapes like lines, rectangles and circles. The snippet shows you how to select colors and then draw a few simple shapes. Use help(wx.PaintDC) to get information about the many things you can use this surface for.

# draw lines, a rounded-rectangle and a circle on a wx.PaintDC() surface
# tested with Python24 and wxPython26     vegaseat      06mar2007

import wx 

class MyFrame(wx.Frame): 
    """a frame with a panel"""
    def __init__(self, parent=None, id=-1, title=None): 
        wx.Frame.__init__(self, parent, id, title) 
        self.panel = wx.Panel(self, size=(350, 200)) 
        self.panel.Bind(wx.EVT_PAINT, self.on_paint) 

    def on_paint(self, event):
        # establish the painting surface
        dc = wx.PaintDC(self.panel)
        dc.SetPen(wx.Pen('blue', 4))
        # draw a blue line (thickness = 4)
        dc.DrawLine(50, 20, 300, 20)
        dc.SetPen(wx.Pen('red', 1))
        # draw a red rounded-rectangle
        rect = wx.Rect(50, 50, 100, 100) 
        dc.DrawRoundedRectangleRect(rect, 8)
        # draw a red circle with yellow fill
        x = 250
        y = 100
        r = 50
        dc.DrawCircle(x, y, r)

# test it ...
app = wx.PySimpleApp() 
frame1 = MyFrame(title='rounded-rectangle & circle')