title: Why am I not able to plot separate bar chart for each product (in dataset) in the same chart using matplotlib?
body: <p>My dataset is something like this.</p>
  <p><img src="https://i.stack.imgur.com/l25rI.png" alt="Image of dataset" /></p>
  <p>I want to Read face cream and face wash product sales data and show it using the bar chart
  and the bar chart should display the number of units sold per month for each product and Add a separate bar for each product in the same chart.</p>
  <p>Code:</p>
  <pre><code>import matplotlib.pyplot as plt
  import numpy as np
  ax = plt.subplot(111)
  ax.bar(x=df['facecream'], y=df['total_units'], height=0.5)
  ax.bar(x=df['facewash'], z=df['total_units'], height=0.5)
  plt.show()
  </code></pre>
  <p>Error:</p>
  <pre><code>ValueError: setting an array element with a sequence.
  </code></pre>