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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def load_from_dict(self, dictionary, _override=True, _allow_undeclared=False):
 """Loads the config with values from a dictionary instead of a file. This is meant for testing and bin purposes and shouldn't be used in most applications. Args: dictionary: The dictionary containing config keys/values to update. _override: If True, new values will override previous values. _allow_undeclared: If True, silently load undeclared keys, otherwise warn and ignore the value. Typically used for loading config files before declarations have been evaluated. """

    undeclared_keys = []
    for key, value in self._modules['six'].iteritems(dictionary):
      # Warn in this case.  We raise if you try to access a config key that
      # hasn't been declared, but we don't raise here so that you can use
      # configuration files that are supersets of required configuration for
      # any particular test station.
      if key not in self._declarations and not _allow_undeclared:
        undeclared_keys.append(key)
        continue
      if key in self._loaded_values:
        if _override:
          self._logger.info(
              'Overriding previously loaded value for %s (%s) with value: %s',
              key, self._loaded_values[key], value)
        else:
          self._logger.info(
              'Ignoring new value (%s), keeping previous value for %s: %s',
              value, key, self._loaded_values[key])
          continue

      # Force any keys and values that are bytes to unicode.
      key = key.decode() if isinstance(key, bytes) else key
      value = value.decode() if isinstance(value, bytes) else value

      self._loaded_values[key] = value
    if undeclared_keys:
      self._logger.warning('Ignoring undeclared configuration keys: %s',
                           undeclared_keys)