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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 prune_volumes(self, filters=None):
 """ Delete unused volumes Args: filters (dict):
 Filters to process on the prune list. Returns: (dict):
 A dict containing a list of deleted volume names and the amount of disk space reclaimed in bytes. Raises: :py:class:`docker.errors.APIError` If the server returns an error. """

        params = {}
        if filters:
            params['filters'] = utils.convert_filters(filters)
        url = self._url('/volumes/prune')
        return self._result(self._post(url, params=params), True)