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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 find_packages_requirements_dists(pkg_names, working_set=None):
 """ Return the entire list of dependency requirements, reversed from the bottom. """


    working_set = working_set or default_working_set
    requirements = [
        r for r in (Requirement.parse(req) for req in pkg_names)
        if working_set.find(r)
    ]
    return list(reversed(working_set.resolve(requirements)))