Geosys is the acronym Geological Systems. In current version, it is small package which contains only one function. The function converts GPS coordinates (longitude, latitude and altitude) to cartesian system. Used referenced ellipsoid is WSG 84 (also known as WGS 1984, EPSG:4326).
pip install geosys
import geosys
latitude = 49.2002211
longitude = 16.6078411
altitude = 0
vertex = geosys.to_cartesian(latitude, longitude, altitude)
# Vertex attributes
# vertex.x
# vertex.y
# vertex.z
print(vertex)
>>> [4001412.65349505, 1193469.21673459, 4805137.77147738]