Implementation-dependent helper function. Will be passed a match object corresponding to the interpolation key we just found (e.g., "%(foo)s" or "$foo"). Should look up that key in the appropriate config file section (using the ``_fetch()`` helper function) and return a 3-tuple: (key, value, section) ``key`` is the name of the key we're looking for ``value`` is the value found for that key ``section`` is a reference to the section where it was found ``key`` and ``section`` should be None if no further interpolation should be performed on the resulting value (e.g., if we interpolated "$$" and returned "$").
Reimplemented from configobj::InterpolationEngine.
: # Valid name (in or out of braces): fetch value from section key = match.group('named') or match.group('braced') if key is not None: value, section = self._fetch(key) return key, value, section # Escaped delimiter (e.g., $$): return single delimiter if match.group('escaped') is not None: # Return None for key and section to indicate it's time to stop return None, self._delimiter, None # Anything else: ignore completely, just return it unchanged return None, match.group(), None