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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 conflicting_deps(tree):
 """Returns dependencies which are not present or conflict with the requirements of other packages. e.g. will warn if pkg1 requires pkg2==2.0 and pkg2==1.0 is installed :param tree: the requirements tree (dict) :returns: dict of DistPackage -> list of unsatisfied/unknown ReqPackage :rtype: dict """

    conflicting = defaultdict(list)
    for p, rs in tree.items():
        for req in rs:
            if req.is_conflicting():
                conflicting[p].append(req)
    return conflicting