python programming

Question 3 Write a program that translates a letter grade into a numeric grade. Assume that the grades are A, B, C, D and Fand that, except for the Fletter grade, each letter grade can possibly be followed by a plus or a minus sign. The numeric grade for A, B, C, D and Fis 4, 3, 2, 1 and 0, respectively. A plus sign after the letter grade for B, C, Dincreases the numeric value of the grade by 0.3; for an A+, the grade is still 4.0 (the maximum grade). A minus sign after the letter grade decreases the numeric value of the grade by 0.3 points for A, B, C, D. Call the file containing your program, numericGrades.py. Don't forget to use "constant" values for known amounts. You may assume the user will never enter F+ or F