Plotting probability distributions

Code given in section 4.3.1 Uniform Distribution

import numpy as np
from utilities import plot_distro

# set range limits
a = 2
b = 6
# set x values
x = np.arange(a,b,0.01)
# set value p = 1/b-a for all values
y = [((b-a)**(-1)) for i in range(len(x)-2)]

plot_distro(x,y,'uniform')

When trying to run this code I get the message: Import error: cannot import name plot_distro
I can find no mention of a function called plot_distro under Python topics on the internet.
Can someone help me run this code.
Thanks, Tom

This plot_distro is possibly part of some custom code that was copied earlier in the program.

Did you start the course from the beginning?