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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 __check_properties(props):
 # type: (dict) -> None """ Checks that the given dictionary doesn't have export keys and has import keys :param props: Properties to validate :raise ValueError: Invalid properties """

        # Mandatory properties
        mandatory = (
            pelix.remote.PROP_ENDPOINT_ID,
            pelix.remote.PROP_IMPORTED_CONFIGS,
            pelix.constants.OBJECTCLASS,
        )
        for key in mandatory:
            if key not in props:
                raise ValueError("Missing property: {0}".format(key))

        # Export/Import properties
        props_export = (
            pelix.remote.PROP_EXPORTED_CONFIGS,
            pelix.remote.PROP_EXPORTED_INTERFACES,
        )

        for key in props_export:
            if key in props:
                raise ValueError("Export property found: {0}".format(key))