The code is not equivalent to Common Lisp (neither is Haskell version), it should remove `count` of elements from the `start` matching a predicate

    (remove-if-not #'evenp '(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15) :count 5 :start 3)
    (1 2 3 4 6 8 10 12 14 15)

    a = (1..15)
    r = []
    c = []
    a.each.with_index do |e, i|
      if i <= 3
        r << e 
      elsif c.length < 5
        if e.even?
          r << e
        else
          c << e
        end
      else
        r << e
      end
    end
    r
    #=> [1, 2, 3, 4, 6, 8, 10, 12, 14, 15]

I can see no simple way to compose this

    a = (1..15)
    l = a.take(3)

    c = 0
    m = a.drop(3).map.with_index { |e, i| [e, i, e.even?] }.take_while { |e, i, p| c +=1 unless p; c <= 5 }
    _, last_m_index, _ = m.last
    m = m.filter { |e, i, p| p }.map { |e, i, p| e }

    r = a.drop(3 + last_m_index + 1)
    l + m + r
    #=> [1, 2, 3, 4, 6, 8, 10, 12, 14, 15]

in Python 3 both range and filter are lazy

but the slices here would spoil it

there is https://docs.python.org/3/library/itertools.html#itertools.i... islice however...