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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 get(self, path, default=_NoDefault, as_type=None, resolve_references=True):
 """ Gets a value for the specified path. :param path: the configuration key to fetch a value for, steps separated by the separator supplied to the constructor (default ``.``) :param default: a value to return if no value is found for the supplied path (``None`` is allowed) :param as_type: an optional callable to apply to the value found for the supplied path (possibly raising exceptions of its own if the value can not be coerced to the expected type) :param resolve_references: whether to resolve references in values :return: the value associated with the supplied configuration key, if available, or a supplied default value if the key was not found :raises ConfigurationError: when no value was found for *path* and *default* was not provided or a reference could not be resolved """

        value = self._source
        steps_taken = []
        try:
            # walk through the values dictionary
            for step in path.split(self._separator):
                steps_taken.append(step)
                value = value[step]

            if as_type:
                return as_type(value)
            elif isinstance(value, Mapping):
                # create an instance of our current type, copying 'configured' properties / policies
                namespace = type(self)(separator=self._separator, missing=self._missing)
                namespace._source = value
                # carry the root object from namespace to namespace, references are always resolved from root
                namespace._root = self._root
                return namespace
            elif resolve_references and isinstance(value, str):
                # only resolve references in str-type values (the only way they can be expressed)
                return self._resolve(value)
            else:
                return value
        except ConfiguredReferenceError:
            # also a KeyError, but this one should bubble to caller
            raise
        except KeyError as e:
            if default is not _NoDefault:
                return default
            else:
                missing_key = self._separator.join(steps_taken)
                raise NotConfiguredError('no configuration for key {}'.format(missing_key), key=missing_key) from e