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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 _list_dict(l: Iterator[str], case_insensitive: bool = False):
 """ return a dictionary with all items of l being the keys of the dictionary If argument case_insensitive is non-zero ldap.cidict.cidict will be used for case-insensitive string keys """

    if case_insensitive:
        raise NotImplementedError()
        d = tldap.dict.CaseInsensitiveDict()
    else:
        d = {}
    for i in l:
        d[i] = None
    return d