ari.py

def ari(s):
    town = []
    s = [c for c in s] + [None]
    for a,b in zip(s, s[1:]):
        if a != b:
            town.append(a)
    return ''.join(town)


if __name__ == '__main__':

    s = "foooooooooooo baaaaaaaaaaaaar"

    print s
    print ari(s)

My method looked something like this:

def squash_adjacent_duplicate_chars(string)
  string.size.times.map do |i|
    string[i] unless string[i + 1] == string[i]
  end.flatten.join
end

this was the solution that seemed most obvious, and which I'd do if it was a one-off in the repl, but zip is just too cool so I did it that way

def ariobv(s):
    town = [s[0]]
    for c in s:
        if c != town[-1]:
            town.append(c)
    return town