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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_subresource(self, subresource, key_name='', headers=None, version_id=None):
 """ Get a subresource for a bucket or key. :type subresource: string :param subresource: The subresource to get. :type key_name: string :param key_name: The key to operate on, or None to operate on the bucket. :type headers: dict :param headers: Additional HTTP headers to include in the request. :type src_version_id: string :param src_version_id: Optional. The version id of the key to operate on. If not specified, operate on the newest version. :rtype: string :returns: The value of the subresource. """

        if not subresource:
            raise TypeError('get_subresource called with subresource=None')
        query_args = subresource
        if version_id:
            query_args += '&versionId=%s' % version_id
        response = self.connection.make_request('GET', self.name, key_name,
                                                query_args=query_args,
                                                headers=headers)
        body = response.read()
        if response.status != 200:
            raise self.connection.provider.storage_response_error(
                response.status, response.reason, body)
        return body