# Author: Sandeep Belgavi. Synthetic exercise; no network or provider calls.
def choose(counts,threshold=0.65,minimum=10):
    total=sum(counts.values())
    if total<minimum:return "Coordinator"
    scores={a:(n+1)/(total+len(counts)) for a,n in counts.items()}
    best=sorted(scores,key=lambda a:(-scores[a],a))[0]
    return best if scores[best]>=threshold else "Coordinator"
counts={"Tester":8,"Coder":1,"Reviewer":1}
assert choose(counts)=="Tester"
assert choose(counts,0.75)=="Coordinator"
assert choose({"Tester":2,"Coder":0})=="Coordinator"
print("Tester; fallback at stricter threshold; fallback with sparse data")