```python
import DREAM.Settings.Equations.RunawayElectrons as Runaways
import DREAM.Settings.Solver as Solver
import DREAM.Settings.CollisionHandler as Collisions
import DREAM.Settings.Equations.ColdElectronTemperature as Temperature
import DREAM.Settings.Equations.ElectricField as ElectricField
import DREAM.Settings.Equations.HotTailGrid as HotTail
import DREAM.Settings.Equations.Ions as Ions
import DREAM.Settings.RadialGrid as RadialGrid
import DREAM.Settings.TimeStepper as TimeStepper
import DREAM

ds = DREAM.Settings.DREAMSettings()

# Electric field
ds.eqsys.E_field.setPrescribedData(0.6)

# Electron density
ds.eqsys.n_cold.setType(Temperature.TYPE_SELFCONSISTENT)
ds.eqsys.n_cold.setInitialProfile(5e19)

# Temperature
ds.eqsys.T_cold.setType(Temperature.TYPE_SELFCONSISTENT)
ds.eqsys.T_cold.setInitialProfile(1e3)

# Disable hot-tail grid
ds.hottailgrid.setEnabled(False)

# Collision frequency mode
ds.collisions.collfreq_mode = Collisions.COLLFREQ_MODE_ULTRA_RELATIVISTIC

# Fully ionized ion species 'D' with charge 1
ds.eqsys.n_i.addIon(name='D', Z=1, iontype=Ions.IONS_DYNAMIC_FULLY_IONIZED, n=5e19)

# Dreicer and avalanche
ds.eqsys.n_re.setAvalanche(Runaways.AVALANCHE_MODE_FLUID)
ds.eqsys.n_re.setDreicer(Runaways.DREICER_RATE_NEURAL_NETWORK)

# Initial profile for runaway electrons
ds.eqsys.n_re.setInitialProfile(1e15)

# Runaway electron grid settings
ds.runawaygrid.setEnabled(True)
ds.runawaygrid.setNp(100)
ds.runawaygrid.setNxi(50)
ds.runawaygrid.setPmax(0.5)

# Advection interpolation method
ds.eqsys.f_hot.setAdvectionInterpolationMethod(ad_int=HotTail.AD_INTERP_FLUX_LIMITER)

# Initialization method
ds.eqsys.f_hot.setInitialDistribution(isotropic=True)

# Radial grid settings
ds.radialgrid.setB0(5)
ds.radialgrid.setMinorRadius(0.22)
ds.radialgrid.setWallRadius(0.22)
ds.radialgrid.setNr(1)

# Solver settings
ds.solver.setType(Solver.NONLINEAR)
ds.solver.setVerbose(True)
ds.solver.setTolerance(reltol=1e-4)

# Include fluid effects
ds.eqsys.n_re.setIncludeFluid(True)

# Time stepper settings
ds.timestep.setTmax(1e-1)
ds.timestep.setNt(20)

# Save settings to HDF5
ds.save('dream_settings.h5')
```