parameters: (self, filename)
docstring: Parse the OpenType language system tag registry.
  
  		Args:
  			filename (str): The file name of the registry.
docstring_summary: Parse the OpenType language system tag registry.
docstring_tokens: Parse the OpenType language system tag registry .
function: def parse (self, filename):
  		"""Parse the OpenType language system tag registry.
  
  		Args:
  			filename (str): The file name of the registry.
  		"""
  		with open (filename, encoding='utf-8') as f:
  			self.feed (f.read ())
  		expect (self.header)
  		for tag, iso_codes in self.to_bcp_47.items ():
  			for iso_code in iso_codes:
  				self.from_bcp_47[iso_code].add (tag)
function_tokens: def parse ( self , filename ) : with open ( filename , encoding = 'utf-8' ) as f : self . feed ( f . read ( ) ) expect ( self . header ) for tag , iso_codes in self . to_bcp_47 . items ( ) : for iso_code in iso_codes : self . from_bcp_47 [ iso_code ] . add ( tag )