python - Python replace method

Question

I write the code below but replace method is not working.

code:

courses = input("Please enter the courses you have taken previously with letter grades: ")
courses.replace("M","X")
print(courses)

Please enter the courses you have taken previously with letter grades:

MATH101:A;SPS101:B;CS201:B+;HIST191:D;CS204:F;CS210:S:
MATH101:A;SPS101:B;CS201:B+;HIST191:D;CS204:F;CS210:S:

标签： pythonmethodsreplace

Answer 1

replace 不会在原地改变字符串。str.replace()

courses = courses.replace("M", "X")