title: how can I plot 4 histograms on the same graph
body: <p><br>I have the following problem:
  <br>I am using hist() in matplotlib.pyplot 
  <br>I am trying to create 4 histograms on the same graph. and an approximation gaussian for each one of them.
  <br>how can I plot the 4 histograms on the same graph, without them blocking each other (side by side)? any ideas?</p>