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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def mutationhash(strings, nedit):
 """ produce a hash with each key a nedit distance substitution for a set of strings. values of the hash is the set of strings the substitution could have come from """

    maxlen = max([len(string) for string in strings])
    indexes = generate_idx(maxlen, nedit)
    muthash = defaultdict(set)
    for string in strings:
        muthash[string].update([string])
        for x in substitution_set(string, indexes):
            muthash[x].update([string])
    return muthash