How to print the tuples in a more user-friendly way

The code:

#This is the second version of the marks analysis program
L = [] #This list will contain both marks and subject
S = []
M = []#This list will only contain marks, for calculation purpose
def help_dialogue():
    print("================HELP DIALOGUE=================")
    print("Press 1 to add marks to the list ")
    print("Press 2 to delete recent marks")
    print("Press 3 to display mark list")
    print("Press 4 to display total marks")
    print("Press 5 to display average marks")
    print("Press 6 to exit (Changes will not be saved")
    print("Press 7 to show help dialogue again")
    print("==============================================")
def add_marks():
    sub = input("Enter Subject name : ")
    marks = int(input("Enter Marks : "))
    L.append((sub, marks))
    S.append(sub)
    M.append(marks)
def print_marksheet():
    print(L)
def average_marks():
    y = sum(M)/len(M)
    return y
def total_marks():
    c = (sum(M))
    return c
def delete_recent_marks():
    L.pop()
    M.pop()
help_dialogue()
while True:
  choice = int(input("Enter your choice: "))
  if choice == 1:
      add_marks()
  elif choice == 2:
    delete_recent_marks()
  elif choice == 3:
    print_marksheet()
  elif choice == 4:
    print(f"The total marks is {total_marks()}")
  elif choice == 5:
    print(f"The average marks is {average_marks()}")
  elif choice == 6:
      break
  elif choice == 7:
      help_dialogue()
  else:
    print("Invalid choice")
print("Thank you for using this program")

In line 22

def print_marksheet():
    print(L)

It just plainly prints the tuples (as expected from the code). But I want the code to print it in a more user-friendly way.

Input:

L = [('English', 78) , ('Mathematics', 99)]

Output:

English => 78  
Mathematics => 99

I tried at first using a for-loop:

def print_marksheet():
  for subject in range(S):

But I realized that the for-loop wasn't looping for the string and asked for an integer. Here is the error I got:

Traceback (most recent call last):
File "C:\\Users\\v\*\*\*\\PycharmProjects\\PythonProject\\Marks analysis_v2.py", line 42, in \<module\>
print_marksheet()
\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~^^
File "C:\\Users\\v\*\*\*\*\\PycharmProjects\\PythonProject\\Marks analysis_v2.py", line 23, in print_marksheet
for subject in range (L):
\~\~\~\~\~\~^^^
TypeError: 'list' object cannot be interpreted as an integer

I searched the internet and found the command enumerate(), but I don't think so it would work for me. (And just in case this command works then please explain how to use it.)

How can I implement the user-friendly output?

Solution

The general way to iterate in Python is:

for item in iterable:
    ...

Here, iterable is your list L. To take it one step further, since the items are tuples, you can decompose them into elements right away:

for sub, marks in L:
    ...

To print the data in a user-friendly way, use a f-string:

for sub, marks in L:
    print(f"For subject {sub} the mark is {marks}")

enumerate is used to assign a numeric index to each item. You could use it if you wanted your output to contain indexing, like this:

1. For subject English the mark is 78
2. For subject Mathematics the mark is 99