title: pycountry currencies returning none
body: <p>My code:</p>
  <pre><code>from pycountry import countries, currencies
  import random
  
  rnum=random.randint(0,100)
  z=list(countries)[rnum]
  y=currencies.get(alpha_3=f'{z.alpha_3}')
  print(f'Currency of {z.name} is {y.name}')
  
  print(z.alpha_3)
  </code></pre>
  <p>Why currencies always returns none!?
  It should return currency details (according to docs)
  but it always returns none.</p>