How to check if a file is empty? python

Question

I have a code that i am writing to read a txt file and report sum, average, ect... but I also need it to recognize when the txt file is empty or has no numbers in it, and not crash. i have tried os.stat(f).st_size == 0, and os.path.getsize(f) == 0:, and reading the first character too. for some reason my code is not picking up on the exception and keeps continuing on with the rest of the code and then crashes when trying to divide by zero to find the average. I am also not using any external libraries.

#the below code asks for the file name and opens the file :)
while (True):
    try:
        filename = input("What file would you like to acess?: ")
        f = open(filename, "r")
    except  IOError:
        print("File", filename, "could not be opened")
    except:
        if os.path.getsize(f) == 0:
            print("There are no numbers in", filename)
    else:
        break
    
#the below line displays the file name :)
print("File Name: ", f.name)

#the below code calculates the sum and prints it :)
sum=0
for n in f:
    n=n.strip()
    sum=sum+int(n)
print("Sum: ", sum)

#the below code calculates the number of lines and prints it :)
with open(filename, "r") as f:
    count = 0
    for line in f:
        if line != "\n":
            count += 1
print("Count: ", count)

#the below code calculates the average and prints it :)
avg = sum/count
print("Average: ", avg)