ASCII Hangman in Progress
Python 2, 215 192 184 183 bytes

-8 bytes thanks to Raphaël Côté
-1 byte thanks to Jonathan Frech


a,b=input()
j=' '.join
s=b-set(a)
print"""  +---+
  |   |
  %s   |
 %s%s%s  |
 %s %s  |
      |
=========
"""%tuple('O/|\/\\'[:len(s)].ljust(6)),j(['_',i][i in b]for i in a),'\n',j(s)


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