title: python plt.bar concatenate error
body: <p>i have 2 lists and i want to put them together in a pyplot.bar</p>
  
  <pre><code>sorted_ratings2 = ['8,3','8,2','8,2','8,3','8,5','8,4','8,2','8,5', '8,2','8,2']
  
  Year = ['1921','1925','1926','1927','1931','1931','1934','1936','1939','1939','1939']
  
  
  
  plt.bar((Year), (sorted_ratings2)
  plt.suptitle('Ratings based on years', fontsize=14)
  plt.ylabel('Rating', fontsize=12)
  plt.xlabel('Year', fontsize=12)  
  plt.show()
  
  
  Output: cannot concatenate 'str' and 'float' objects
  </code></pre>
  
  <p>i try to plot with plt.bar but get this error.  what do i do wrong?</p>