def _maybe_append_formatted_extension(numobj, metadata, num_format, number):
 if numobj.extension:
  if (num_format == PhoneNumberFormat.RFC3966):
   return ((number + _RFC3966_EXTN_PREFIX) + numobj.extension)
  elif (metadata.preferred_extn_prefix is not None):
   return ((number + metadata.preferred_extn_prefix) + numobj.extension)
  else:
   return ((number + _DEFAULT_EXTN_PREFIX) + numobj.extension)
 return number

def _maybe_append_formatted_extension ( numobj , metadata , num_format , number ) : if numobj . extension : if ( num_format == PhoneNumberFormat . RFC3966 ) : return ( ( number + _RFC3966_EXTN_PREFIX ) + numobj . extension ) elif ( metadata . preferred_extn_prefix is not None ) : return ( ( number + metadata . preferred_extn_prefix ) + numobj . extension ) else : return ( ( number + _DEFAULT_EXTN_PREFIX ) + numobj . extension ) return number
appends the formatted extension of a phone number to formatted number .