text = "lorem ipsum buzz mezzo mix zztop but this is all"
words = [word
for word in text.split()
if not (word.startswith("zz") or word.endswith("zz")) and "zz" in word]
print(words)
dGV4dCA9ICJsb3JlbSBpcHN1bSBidXp6IG1lenpvIG1peCB6enRvcCBidXQgdGhpcyBpcyBhbGwiCgp3b3JkcyA9IFt3b3JkIAoJCSBmb3Igd29yZCBpbiB0ZXh0LnNwbGl0KCkKCQkgaWYgbm90ICh3b3JkLnN0YXJ0c3dpdGgoInp6Iikgb3Igd29yZC5lbmRzd2l0aCgienoiKSkgYW5kICJ6eiIgaW4gd29yZF0KCnByaW50KHdvcmRzKQ==