title: Command window in Pycharm
body: <p>Is there a interface in Pycharm where we can simply type in some commands and run it ? 
  Something like in Matlab, we can type in "a = 1; b = 2; c = a+b" then we get ans=3.</p>
  
  <p>Thanks
  PS: we know we can create a python file in Pycharm and run it, e.g., "a = 1; b = 2; c = a+b; print(c)" but it is not as convenient as a command window.</p>