code: def parse(self, rrstr):
          # type: (bytes) -> None
          '''
          Parse a Rock Ridge Platform Dependent record out of a string.
  
          Parameters:
           rrstr - The string to parse the record out of.
          Returns:
           Nothing.
          '''
          if self._initialized:
              raise pycdlibexception.PyCdlibInternalError('PD record already initialized!')
  
          (su_len_unused, su_entry_version_unused) = struct.unpack_from('=BB', rrstr[:4], 2)
  
          self.padding = rrstr[4:]
  
          # We assume that the caller has already checked the su_entry_version,
          # so we don't bother.
  
          self._initialized = Truf parse(self, rrstr):
          # type: (bytes) -> None
          '''
          Parse a Rock Ridge Platform Dependent record out of a string.
  
          Parameters:
           rrstr - The string to parse the record out of.
          Returns:
           Nothing.
          '''
          if self._initialized:
              raise pycdlibexception.PyCdlibInternalError('PD record already initialized!')
  
          (su_len_unused, su_entry_version_unused) = struct.unpack_from('=BB', rrstr[:4], 2)
  
          self.padding = rrstr[4:]
  
          # We assume that the caller has already checked the su_entry_version,
          # so we don't bother.
  
          self._initialized = True
docs: Parse a Rock Ridge Platform Dependent record out of a string.
  
          Parameters:
           rrstr - The string to parse the record out of.
          Returns:
           Nothing.