A light horizontal grid behind the bars and tidy spines

Draw a vertical bar chart of the weight (kg) of recyclables collected on campus this month, by material. Put the bars in the order of materials. The title is Recycling collected this month, and the y-axis label is Weight (kg).

To make the bar heights easy to read, draw only light horizontal grid lines and no vertical grid lines. Put the grid behind the bars with set_axisbelow(True).

Hide the top and right spines, and keep the left and bottom spines, which serve as the reference for the values.

Starter code

import matplotlib.pyplot as plt

materials = ["Paper", "Plastic", "Glass", "Can"]
weights = [320, 210, 150, 90]

# Write your code here