async def get(self,request_configuration: Optional[RequestConfiguration[MailboxProtectionUnitsRequestBuilderGetQueryParameters]] = None) -> Optional[MailboxProtectionUnitCollectionResponse]:
        """
        The protection units (mailboxes) that are  protected under the Exchange protection policy.
        param request_configuration: Configuration for the request such as headers, query parameters, and middleware options.
        Returns: Optional[MailboxProtectionUnitCollectionResponse]
        """
        request_info = self.to_get_request_information(
            request_configuration
        )
        from ......models.o_data_errors.o_data_error import ODataError

        error_mapping: dict[str, type[ParsableFactory]] = {
            "XXX": ODataError,
        }
        if not self.request_adapter:
            raise Exception("Http core is null") 
        from ......models.mailbox_protection_unit_collection_response import MailboxProtectionUnitCollectionResponse

        return await self.request_adapter.send_async(request_info, MailboxProtectionUnitCollectionResponse, error_mapping)

        The protection units (mailboxes) that are  protected under the Exchange protection policy.
        param request_configuration: Configuration for the request such as headers, query parameters, and middleware options.
        Returns: Optional[MailboxProtectionUnitCollectionResponse]
        
msgraph/generated/solutions/backup_restore/exchange_protection_policies/item/mailbox_protection_units/mailbox_protection_units_request_builder.py