def strings(count):

    for _ in range(count):

        yield "aba"

def match_ends(words):

    return len( [word for word in words if len(word)>=2 and word[0] == word[-1] ] )

match_ends2 = lambda ws: sum(len(w) >= 2 and w[0] == w[-1] for w in ws)

print(match_ends(strings(10 ** 9)))