class std:
    roll = ""
    gpa = ""

rahim = std()
#print(isinstance(rahim.std))
rahim.roll = 101
rahim. gpa = 3.78

print(f"Roll:{rahim.roll},GPA:{rahim.gpa}")


ahim = std()
#print(isinstance(ahim.std))
ahim.roll = 101
ahim. gpa = 3.78
print(f"Roll:{ahim.roll},GPA:{ahim.gpa}")