How can I join a list of strings and remove duplicated letters (keep them chained)

Question

My list:

l = ["volcano", "noway", "lease", "sequence", "erupt"]

Desired output:

'volcanowayleasequencerupt'

I have tried:

using itertools.groupby but it seems like it doesn't work well when there is 2 repeated letters in row (i.e. leasesequence -> sese stays):

>>> from itertools import groupby
>>> "".join([i[0] for i in groupby("".join(l))])
'volcanonowayleasesequencerupt'

As you can see it got rid only for the last 'e', and this is not ideal because if a letter has double characters they will be shrunk to 1. i.e 'suddenly' becomes 'sudenly'.

I'm looking for the most Pythonic approach for this.

Thank you in advance.

EDIT

My list does not have any duplicated items in it.

Answer 1

Using a helper function that crops a word t by removing its longest prefix that's also a suffix of s:

def crop(s, t):
    for k in range(len(t), -1, -1):
        if s.endswith(t[:k]):
            return t[k:]

And then crop each word with its preceding word:

>>> l = ["volcano", "noway", "lease", "sequence", "erupt"]
>>> ''.join(crop(s, t) for s, t in zip([''] + l, l))
'volcanowayleasequencerupt'

>>> l = ['split', 'it', 'lit']
>>> ''.join(crop(s, t) for s, t in zip([''] + l, l))
'splitlit'