Adding image to a plot

Hi,
I am trying to insert a .png image to the right side of the plot and following the code mentioned here:Combine picture and plot with Python Matplotlib

Here is what I have tried:

import numpy as np
from matplotlib.colors import LinearSegmentedColormap
import matplotlib.pyplot as plt
import matplotlib as mpl
import matplotlib.cbook as cbook
from matplotlib._png import read_png
from matplotlib.offsetbox import OffsetImage
cmap = mpl.cm.hot
norm = mpl.colors.Normalize(vmin=-1 * outlier, vmax=outlier)
cmap.set_over('green')
cmap.set_under('green')
cmap.set_bad('green')
plt.xlim(0,35)
plt.ylim(0,35)
fig, ax = plt.subplots()
ax.set_aspect('equal')
cb_ax=fig.add_axes([0.85, 0.1, 0.03, 0.8])
img = ax.imshow(np.ma.masked_values(data, outlier), cmap=cmap, norm=norm, interpolation='none',vmax=outlier)
cb = mpl.colorbar.ColorbarBase(cb_ax, cmap=cmap, norm=norm, extend='both')
##axim = plt.subplot2grid(shape, loc, rowspan=1)

## phlo tree
image_file = cbook.get_sample_data('mytree.png',asfileobj=False)
image = plt.imread(image_file)
phyl_ax=fig.add_axes([0.10,0.1, 0.03, 0.8])
phyl_ax.imshow(image,interpolation='nearest')
Th heat map would be on the left side and the image of a tree will be inserted on the right side. The above code gives me the required heat map but the image I am trying to add on the right side isn't appearing. Can someone lead me as to how I can go about this?

Thanks