import netCDF4
import numpy as np

str_out = netCDF4.stringtochar(np.array(['test'], 'S4'))

nc = netCDF4.Dataset('./test.nc', 'w', format='NETCDF4_CLASSIC')
nc.createDimension('lat', 1)
nc.createDimension('lon', 1)
nc.createDimension('nchar', 4)

lat = nc.createVariable('lat', 'f4', ('lat',))
lon = nc.createVariable('lon', 'f4', ('lon',))
place = nc.createVariable('place', 'S1', ('nchar'))

lat[:] = 17.002
lon[:] = -81.501
place[:] = str_out

nc.close()