title: multinomial pmf in python scipy/numpy
body: <p>Is there a built-in function in scipy/numpy for getting the PMF of a Multinomial? I'm not sure if <code>binom</code> generalizes in the correct way, e.g.</p>
  
  <pre><code># Attempt to define multinomial with n = 10, p = [0.1, 0.1, 0.8]
  rv = scipy.stats.binom(10, [0.1, 0.1, 0.8])
  # Score the outcome 4, 4, 2
  rv.pmf([4, 4, 2])
  </code></pre>
  
  <p>What is the correct way to do this?  thanks.</p>