I need help in python code using numpy in data science for following exercise

Given the Numpy series on the left below(Key, data). Using Numpy make the following:

a. Split into groups of letters.

b. Sum every group and obtain the final values of A, B, C in one Series

Combine \begin{tabular}{|l|l|} \hline A & 15 \\ \hlineB & 30 \\ \hline C & 45 \\ \hline \end{tabular} \begin{tabular}{|l|l|} \hlineC & 10 \\ \hlineC & 15 \\ \hlineC & 20 \\ \hline \end{tabular}