In one-dimensional list a=[a1, a2, ..., an] all positive elements that have an even sequence number, rewrite the beginning....

Question

In one-dimensional list a=[a1, a2, ..., an] all positive elements that have an even sequence number, rewrite the beginning of the list. in Python

Answer 1

a = [a[i] for i in range(0, len(a)) if i % 2 == 0]