In this task, you are given an input list A. You need to find all the elements of the list that are numbers and calculate their sum.

['2787', 'z', '9351', '3339']
15477

['W', 'O', 'c', 'r', 'E', 'w', '9811', '6421', '3543', '4293', '8255', 't', '229', '745', 'w', 'p', '6861', '5305', 'h']
45463

['1959', '3677', '3799', 'm', 'p', 'w', '9267', 'E', '8903', '195', '1861', '933', '1119', '7807', '9829']

49349