s1 = Series([9, 7, 8])
print(s1)
print()

s2 = Series({"A": 9, "B": 7, "C": 8})
print(s2)
print()

print(s1.sum())
print(s2.iloc[0])
print(s2.loc["A"])

s2.loc["A"] = 100
print(s2)
print()
s2.loc["B"] = 200
print(s2)
print()

s3 = s2.sort_values()
print(s3)
print()

s4 = s3.sort_index()
print(s4)
print()