from pymatgen import MPRester
if __name__ == "__main__":
MAPI_KEY = "XXXXXX" # You must change this to your Materials API key! (or set MAPI_KEY env variable)
with MPRester(MAPI_KEY) as m: # object for connecting to MP Rest interface
criteria ={'elements': {'$all':['Fe', 'O']}}
properties=['pretty_formula', 'full_formula', 'total_magnetization']
data = m.query(criteria, properties)
print(data)
print(len(data))
It prints 4568 elements with their corresponding total magnetization
And just to answer your initial question if you can accomplish this with an URL link and the REST library, the answer is currently no. This is from the API help page
Advanced query using Mongo-like language for flexible queries on the Materials Project database. This provides the possibility of queries which would otherwise not be possible using the other simpler REST forms.