title: FileNotFoundError: [Errno 2] No such file or directory: 'ffmpeg'
body: <p>I'm new in python and i'm using <code>pydub</code> modules to play mp3 track.</p>
  
  <p>Here is my simple code to play mp3:</p>
  
  <pre><code>#Let's play some mp3 files using python!
  
  from pydub import AudioSegment
  from pydub.playback import play
  
  song = AudioSegment.from_mp3("/media/rajendra/0C86E11786E10256/05_I_Like_It_Rough.mp3")
  play(song)
  </code></pre>
  
  <p>When i run this program, it says:</p>
  
  <pre><code>*/usr/bin/python3.4 /home/rajendra/PycharmProjects/pythonProject5/myProgram.py
  /usr/local/lib/python3.4/dist-packages/pydub/utils.py:161: RuntimeWarning: Couldn't find ffmpeg or avconv - defaulting to ffmpeg, but may not work
    warn("Couldn't find ffmpeg or avconv - defaulting to ffmpeg, but may not work", RuntimeWarning)
  /usr/local/lib/python3.4/dist-packages/pydub/utils.py:174: RuntimeWarning: Couldn't find ffplay or avplay - defaulting to ffplay, but may not work
    warn("Couldn't find ffplay or avplay - defaulting to ffplay, but may not work", RuntimeWarning)
  Traceback (most recent call last):
    File "/home/rajendra/PycharmProjects/pythonProject5/myProgram.py", line 11, in &lt;module&gt;
      song = AudioSegment.from_mp3("/media/rajendra/0C86E11786E10256/05_I_Like_It_Rough.mp3")
    File "/usr/local/lib/python3.4/dist-packages/pydub/audio_segment.py", line 355, in from_mp3
      return cls.from_file(file, 'mp3')
    File "/usr/local/lib/python3.4/dist-packages/pydub/audio_segment.py", line 339, in from_file
      retcode = subprocess.call(convertion_command, stderr=open(os.devnull))
    File "/usr/lib/python3.4/subprocess.py", line 533, in call
      with Popen(*popenargs, **kwargs) as p:
    File "/usr/lib/python3.4/subprocess.py", line 848, in __init__
      restore_signals, start_new_session)
    File "/usr/lib/python3.4/subprocess.py", line 1446, in _execute_child
      raise child_exception_type(errno_num, err_msg)
  FileNotFoundError: [Errno 2] No such file or directory: 'ffmpeg'
  
  Process finished with exit code 1*
  </code></pre>
  
  <p>Please help me! I've checked everything path but it's not working. I'm currently using Ubuntu. </p>
  
  <p>Help would be appreciated!</p>