Delete attributes from a given item.

        :type item_name: string
        :param item_name: The name of the item whose attributes are being deleted.

        :type attributes: dict, list or :class:`boto.sdb.item.Item`
        :param attributes: Either a list containing attribute names which will cause
                           all values associated with that attribute name to be deleted or
                           a dict or Item containing the attribute names and keys and list
                           of values to delete as the value.  If no value is supplied,
                           all attribute name/values for the item will be deleted.
                           
        :type expected_value: list
        :param expected_value: If supplied, this is a list or tuple consisting
            of a single attribute name and expected value. The list can be of 
            the form:

             * ['name', 'value']

            In which case the call will first verify that the attribute "name"
            of this item has a value of "value".  If it does, the delete
            will proceed, otherwise a ConditionalCheckFailed error will be 
            returned. The list can also be of the form:

             * ['name', True|False]

            which will simply check for the existence (True) or 
            non-existence (False) of the attribute.

        :rtype: bool
        :return: True if successful

def delete_attributes(self, item_name, attributes=None,
                          expected_values=None):
        """
        Delete attributes from a given item.

        :type item_name: string
        :param item_name: The name of the item whose attributes are being deleted.

        :type attributes: dict, list or :class:`boto.sdb.item.Item`
        :param attributes: Either a list containing attribute names which will cause
                           all values associated with that attribute name to be deleted or
                           a dict or Item containing the attribute names and keys and list
                           of values to delete as the value.  If no value is supplied,
                           all attribute name/values for the item will be deleted.
                           
        :type expected_value: list
        :param expected_value: If supplied, this is a list or tuple consisting
            of a single attribute name and expected value. The list can be of 
            the form:

             * ['name', 'value']

            In which case the call will first verify that the attribute "name"
            of this item has a value of "value".  If it does, the delete
            will proceed, otherwise a ConditionalCheckFailed error will be 
            returned. The list can also be of the form:

             * ['name', True|False]

            which will simply check for the existence (True) or 
            non-existence (False) of the attribute.

        :rtype: bool
        :return: True if successful
        """
        return self.connection.delete_attributes(self, item_name, attributes,
                                                 expected_values)