list operation

 l1  #list to evaluate

[100, 11, 12, 3, 4, 12, 3, 10, 100, 11, 100, 2, 200]

 // list with  numbers even postion on the list l1

[l1.index(c) for c in [a for a in l1 if  a % 2==0]]

[0, 2, 4, 2, 7, 0, 0, 11, 12]

// list list with the value

[l1[e] for e in [l1.index(c) for c in [a for a in l1 if  a % 2==0]]]

[100, 12, 4, 12, 10, 100, 100, 2, 200]

a dict with index and value

>>> {e:l1[e] for e in [l1.index(c) for c in [a for a in l1 if  a % 2==0]]}

{0: 100, 2: 12, 4: 4, 7: 10, 11: 2, 12: 200}

Or other dict  with  value and index

>>> {l1[e]:l1.index(l1[e]) for e in [l1.index(c) for c in [a for a in l1 if  a % 2==0]]}

{100: 0, 12: 2, 4: 4, 10: 7, 2: 11, 200: 12}

using lambda

>>> test= lambda l1:{e:l1[e] for e in [l1.index(c) for c in [a for a in l1 if  a % 2==0]]}

>>> l2=[100,32,34,13,3]

>>> test(l2)

{0: 100, 1: 32, 2: 34}

>>> test([100,33,53,18,98,67])

{0: 100, 3: 18, 4: 98}

>>>