title: No suggestions for triggers when using Pytransitions
body: <p>Trying to use <code>transitions</code> package as per examples provided here <a href="https://github.com/pytransitions/transitions" rel="nofollow noreferrer">https://github.com/pytransitions/transitions</a></p>
  
  <p>For some reason, neither of the two approaches shown below provide typing suggestions for registered <code>evaporate()</code> trigger (at least in PyCharm 2019.1.2 for Windows x64)</p>
  
  <p>At the same time, these triggers can still be used. </p>
  
  <p>What can be done to have these triggers suggested as I type?</p>
  
  <pre class="lang-py prettyprint-override"><code>class Matter(Machine):
      def say_hello(self): print("hello, new state!")
      def say_goodbye(self): print("goodbye, old state!")
  
      def __init__(self):
          states = ['solid', 'liquid', 'gas']
          Machine.__init__(self, states=states, initial='liquid')
          self.add_transition('melt', 'solid', 'liquid')
  
  testmatter= Matter()
  testmatter.add_transition('evaporate', 'liquid', 'gas')
  testmatter.evaporate()
  Out: True
  
  testmatter.get_model_state(testmatter)
  Out: &lt;State('gas')@14748976&gt;
  </code></pre>
  
  <pre class="lang-py prettyprint-override"><code>class Matter2():
      pass
  testmatter2 = Matter2()
  machine  = Machine(model=testmatter2, states=['solid', 'liquid', 'gas', 'plasma'], initial='liquid')
  machine.add_transition('evaporate', 'liquid', 'gas')
  
  testmatter2.evaporate()
  Out: True
  </code></pre>