Heat map and visualization
I believe that the simplest is to use Seaborn. Check out the example below:

import numpy as np
import seaborn as sns 

sns.set()
np.random.seed(0)

uniform_data = np.random.rand(10, 12)
ax = sns.heatmap(uniform_data)


And the output looks as follows:



This is taken from the seaborn documentation