list1 = IN[0]
listGroups = []
group = []

for index, string in enumerate(list1):
    try:
        if string == list1[index + 1]:
            group.append(string)
        else:
            group.append(string)
            listGroups.append(group)
            group = []
    except IndexError:
        group.append(string)
        listGroups.append(group)

OUT = listGroups