Convert FESOM2 data to UGRID that QGIS3.16.6 can understand

FESOM2_to_UGRID_for_QGIS3.16.6.py

import xarray as xr
import numpy as np
import pyfesom2 as pf

# we make it similar to this file
# ugrid = xr.open_dataset('./MDAL/tests/data/ugrid/ADCIRC/ADCIRC_BG_20190910_1t.nc')

data = xr.open_mfdataset('/Users/nkolduno/PYTHON/DATA/LCORE2/temp.fesom.*.nc')
mesh = pf.load_mesh('/Users/nkolduno/PYTHON/DATA/core2/')

elem2 = mesh.elem[mesh.no_cyclic_elem]

ds = xr.Dataset({'mesh_topology': ( np.array(-2147483647, dtype='int32')),
                 'elem': (["nelem", "three"], elem2.astype('int32')),
                 'variable': (['nod2'], data.temp[0,:,0].astype('float32')),
                },
                 coords={'latitude': (['nod2'], mesh.y2),
                         'longitude': (['nod2'], mesh.x2),
                         
                        })

ds.mesh_topology.attrs = {'long_name': 'mesh topology',
 'standard_name': 'mesh_topology',
 'dimension': 2,
 'node_coordinates': 'longitude latitude',
 'face_node_connectivity': 'elem',
 'cf_role': 'mesh_topology',
 'topology_dimension': 2}

ds.latitude.attrs = {'long_name': 'latitude',
 'standard_name': 'latitude',
 'units': 'degrees_north',
 'positive': 'north'}

ds.longitude.attrs = {'long_name': 'longitude',
 'standard_name': 'longitude',
 'units': 'degrees_east',
 'positive': 'east'}

ds.elem.attrs = {'long_name': 'elem',
 'standard_name': 'face_node_connectivity',
 'units': 'nondimensional',
 'start_index': 0}

ds.attrs = {'Conventions': 'CF-1.6, UGRID-1.0'}

ds.to_netcdf('output.nc')