How to do it...

The following code block defines points and associated lines and curves to be drawn to form the overall picture:

1. Define the points along with the first curve to be drawn

verts1 = [(-1.5, 0.),             # left, bottom
          (0., 1.),               # left, top
          (1.5, 0.),              # right, top
          (0., -1.0),             # right, bottom
          (-1.5, 0.)]             # ignored

2. Plot the graph connecting the points defined in step 1:

codes1 = [Path.MOVETO,    # Go to first point specified in vert1
          Path.LINETO,    # Draw a line from first point to second 
                            point
          Path.LINETO,    # Draw another line from current point to 
                            next point
          Path.LINETO,    # Draw another line from current point to 
                            next point
          Path.CLOSEPOLY] # Close the loop

3. Create the complete path with points and lines/curves defined in step 1 and step 2:

path1 = Path(verts1, codes1)

4. Repeat the same for the second curve:

verts2 = [(-1.5, 0.),       # left, bottom
          (0., 2.5),        # left, top
          (1.5, 0.),        # right, top
          (0., -2.5),       # right, bottom
          (-1.5, 0.)]       # ignored

codes2 = [Path.MOVETO, # Move to the first point
          Path.CURVE3, # Curve from first point along the control 
                         point and terminate on end point
          Path.CURVE3, # Curve from current point along the control 
                         point and terminate on end point
          Path.CURVE3,
          Path.CURVE3] # close by the curved loop

path2 = Path(verts2, codes2)

5. Define the figure and the axes:

fig = plt.figure()
ax = fig.add_subplot(111)

6. Create the first patch and add it to the axes:

patch1 = patches.PathPatch(path1, lw=4, zorder=2)
ax.add_patch(patch1)

7. Create the second patch and add it to the axes:

patch2 = patches.PathPatch(path2, facecolor='orange', lw=2, 
                           zorder=1)
ax.add_patch(patch2)

8. Set the limits for x and y axes:

ax.set_xlim(-2,2)
ax.set_ylim(-2,2)

9. Display the plot on the screen:

plt.show()