Plots getting rid of whitespace
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what you where thinking is right, the new version plot looks a bit different, to get exactly the same plot as above you can use the following code:

import pandas as pd
import matplotlib.pyplot as plt    
df3 = pd.read_csv('df3')
#%matplotlib inline (This line is to be used in jupyter notebooks to display plots)

ax = plt.subplot(111)
ax.hist(df3['a'],ec='black')

#this is x axis limiter since your value ranges in between 0 to 1 I gave these values
plt.xlim([0,1])
plt.show()


Outcome:



Let me know if you need anything else. 

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