  An ultra high energy electromagnetic cascade, a purely leptonic process and
initiated by either photons or $e^\pm$, can be a source of high energy
neutrinos. We present a public python3 code, MUNHECA, to compute the neutrino
spectrum by taking into account various QED processes, with the cascade
developing either along the propagation in the cosmic microwave background in
the high-redshift universe or in a predefined photon background surrounding the
astrophysical source. The user can adjust various settings of MUNHECA,
including the spectrum of injected high energy photons, the background photon
field and the QED processes governing the cascade evolution. We improve the
modeling of several processes, provide examples of the execution of MUNHECA and
compare it with some earlier and more simplified estimates of the neutrino
spectrum from electromagnetic cascades.
