import matplotlib.pyplot as plt
from grizli.utils import SpectrumTemplate

ha = SpectrumTemplate(central_wave=6563., fwhm=10)
plt.plot(ha.wave, ha.flux)

ha_z = ha.zscale(0.1)
plt.plot(ha_z.wave, ha_z.flux, label='z=0.1')

plt.legend()
plt.xlabel(r'$\lambda$')
plt.xlim(6000, 7500)

plt.show()