old_contents: class ffmpeg(Wig):
  	tarball_uri = 'http://ffmpeg.org/releases/ffmpeg-$RELEASE_VERSION$.tar.gz'
  	last_release_version = 'v3.1.2'
  	optional_dependencies = ['yasm', 'x264']
  	supported_features = ['yasm', 'x264']
  	dependencies = ['bzip2', 'lzma']
  	default_features = ['+yasm']
  
  	def switch_yasm_on(self):
  		self.require('yasm')
  		self.configure_flags += ['--yasmexe="$PREFIX/bin/yasm"', '--enable-shared']
  
  	def switch_x264_on(self):
  		self.require('x264')
  		self.configure_flags += ['--enable-gpl', '--enable-libx264']
  
new_contents: class ffmpeg(Wig):
  	tarball_uri = 'http://ffmpeg.org/releases/ffmpeg-$RELEASE_VERSION$.tar.gz'
  	last_release_version = 'v3.1.2'
  	optional_dependencies = ['yasm', 'x264']
  	supported_features = ['yasm', 'x264']
  	dependencies = ['bzip2', 'lzma', 'zlib']
  	default_features = ['+yasm']
  
  	def switch_yasm_on(self):
  		self.require('yasm')
  		self.configure_flags += ['--yasmexe="$PREFIX/bin/yasm"', '--enable-shared']
  
  	def switch_x264_on(self):
  		self.require('x264')
  		self.configure_flags += ['--enable-gpl', '--enable-libx264']
  
subject: Update ffmpeg.py