Write the Python code to find the percentage of B$+$s given in EVERY section of every course at Illinois.

The percentage of B$+$s must be added into a new column called Percent B$+.$ The percentage should be left as a decimal number between $0$ and $1.$ For example, if $10$ B$+$s were given and there were $100$ students in the class, the Percent B$+$ would be equal to $0\mathrm{.}1.$

You can create extra columns if needed, only Percent B$+$ will be graded.

The columns available in the GPA dataset includes:

Year: The year the course was offered

Term: The semester that the course was offered

YearTerm: A combination of the year and term

Subject: The name of the subject that the course falls under $($for ex$.$ "ACCY", $"$CS$",$ etc.$)$

Number: The numeric level of the course $($i$.$e$.100,200,400,400,$ or $500)$

Course Title: The name of the course

Sched Type: The course format $($i$.$e$.$ LCD, LEC, ONL$)$

A$+,$ A$,$ A$-,$ B$+,$ B$,$ B$-,$ C$+,$ C$,$ C$-,$ D$+,$ D$,$ D$-,$ F$,$ W: Each Grade is a column on its own that represents the number of that particular grade for each course $($i$.$e$.$ A$+$ represents the number of A$+\text{'}$s per course$)$

Primary Instructor: The primary instructor of each course

Students: The number of students per course