'Add volume to export group.
:param sync: synchronous request
:param exportgroupname: Name/id of the export group
:param tenantname: tenant name
:param maxpaths: Maximum number of paths
:param minpaths: Minimum number of paths
:param pathsperinitiator: Paths per initiator
:param projectname: name of project
:param volumenames: names of volumes that needs
to be added to exportgroup
:param cg: consistency group
:param synctimeout: Query for task status for \'synctimeout\' secs
If the task doesn\'t complete in synctimeout secs,
an exception is thrown
:param varray: Name of varray
:returns: action result'

def exportgroup_add_volumes(self, sync, exportgroupname, tenantname, maxpaths, minpaths, pathsperinitiator, projectname, volumenames, cg=None, synctimeout=0, varray=None):

    varrayuri = None
    if varray:
        varrayObject = virtualarray.VirtualArray(self.ipaddr, self.port)
        varrayuri = varrayObject.varray_query(varray)
    exportgroup_uri = self.exportgroup_query(exportgroupname, projectname, tenantname, varrayuri)
    if (tenantname is None):
        tenantname = ''
    volume_list = []
    if volumenames:
        volume_list = self._get_resource_lun_tuple(volumenames, 'volumes', None, tenantname, projectname, None)
    parms = {}
    volChanges = {}
    volChanges['add'] = volume_list
    parms['volume_changes'] = volChanges
    o = self.send_json_request(exportgroup_uri, parms)
    return self.check_for_sync(o, sync, synctimeout)
