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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 configure_from_environment(self, whitelist_keys=False, whitelist=None):
 """Configure from the entire set of available environment variables. This is really a shorthand for grabbing ``os.environ`` and passing to :meth:`_configure_from_mapping`. As always, only uppercase keys are loaded. Keyword Args: whitelist_keys (bool):
 Should we whitelist the keys by only pulling those that are already present in the config? Useful for avoiding adding things like ``LESSPIPE`` to your app config. If no whitelist is provided, we use the current config keys as our whitelist. whitelist (list[str]):
 An explicit list of keys that should be allowed. If provided and ``whitelist_keys`` is true, we will use that as our whitelist instead of pre-existing app config keys. Returns: fleaker.base.BaseApplication: Returns itself. """

        self._configure_from_mapping(os.environ, whitelist_keys=whitelist_keys,
                                     whitelist=whitelist)

        return self