def get$\_$grade$\_$input$($grade$\_$dict$)$:

# TODO: Write a function that asks the user for a letter grade. If the letter grade is in the grade$\_$dict, return it$.$ Otherwise, ask the user again for a valid letter grade.

grade $=$ input$("$Enter a grade $($A$+,$ A$,$ A$-,$ B$+,$ B$,$ B$-,$ C$+,$ C$,$ C$-,$ D$+,$ D$,$ F$)$: $").$upper$()$

if grade in grade$\_$dict:

return grade

else:

print$("$Invalid grade. Please enter a valid grade."$)$

def calculate$\_$gpa$($grade$\_$value$\_$list$)$:

# TODO: Write a function that calculates the GPA from a list of GPA values

if not grade$\_$value$\_$list:

return $0\mathrm{.}0$

total$\_$points $=$ sum$($grade$\_$value$\_$list$)$

return total$\_$points $/$ len$($grade$\_$value$\_$list$)$

def main$()$:

# Dictionary that converts letter values to numeric equivalents

grade$\_$dict $=\{\text{'}$A$+\text{'}$:$4\mathrm{.}2,\text{'}$A$\text{'}$:$4,\text{'}$A$-\text{'}$:$3\mathrm{.}7,\text{'}$B$+\text{'}$:$3\mathrm{.}3,\text{'}$B$\text{'}$:$3\mathrm{.}0,\text{'}$B$-\text{'}$:$2\mathrm{.}7,\text{'}$C$+\text{'}$:$2\mathrm{.}3,\text{'}$C$\text{'}$:$2\mathrm{.}0,\text{'}$C$-\text{'}$:$1\mathrm{.}7,\text{'}$D$+\text{'}$:$1\mathrm{.}3,\text{'}$D$\text{'}$:$1\mathrm{.}0,\text{'}$F$\text{'}$:$0\}$

# List of all letter grades entered

grade$\_$list $=[]$

# List of all grade values based on letter grades entered

grade$\_$value$\_$list $=[]$

# TODO: Write the primary logic of your program here

if $\_\_$name$\_\_=="\_\_$main$\_\_"$:

main$()$