TASK DEFINITION: In this task, you are given an input list A. You need to find all the elements of the list that are numbers in the same order as they appear in the list A.
PROBLEM: ['M', '2991', 'k', '6987', '8495', '3953', 'f', 'u', '6621']

SOLUTION: 2991, 6987, 8495, 3953, 6621

PROBLEM: ['2931', '7973', 'z', '4759', 'S', '7525', '2107', '7237']

SOLUTION: 2931, 7973, 4759, 7525, 2107, 7237

PROBLEM: ['R', 'x']

SOLUTION: