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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_queue_acl(self, queue_name, timeout=None):
        '''
        Returns details about any stored access policies specified on the
        queue that may be used with Shared Access Signatures.

        :param str queue_name:
            The name of an existing queue.
        :param int timeout:
            The server timeout, expressed in seconds.
        :return: A dictionary of access policies associated with the queue.
        :rtype: dict of str to :class:`~azure.storage.models.AccessPolicy`
        '''
        _validate_not_none('queue_name', queue_name)
        request = HTTPRequest()
        request.method = 'GET'
        request.host = self._get_host()
        request.path = _get_path(queue_name)
        request.query = [
            ('comp', 'acl'),
            ('timeout', _int_to_str(timeout)),
        ]
        response = self._perform_request(request)

        return _convert_xml_to_signed_identifiers(response.body)