min(i for i in range(len(L)) if L[i:i + len(key)] == key)
L = [0, 8, 5, 6, 4, 5, 6, 14, 8]
key = [4, 5, 6]
min(i for i in range(len(L)) if L[i:i + len(key)] == key)
How do I return the index of multiple elements existing in a list in Python?