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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 _simulate_installation_of(to_install, package_set):
 # type: (List[InstallRequirement], PackageSet) -> Set[str] """Computes the version of packages after installing to_install. """


    # Keep track of packages that were installed
    installed = set()

    # Modify it as installing requirement_set would (assuming no errors)
    for inst_req in to_install:
        dist = make_abstract_dist(inst_req).dist()
        name = canonicalize_name(dist.key)
        package_set[name] = PackageDetails(dist.version, dist.requires())

        installed.add(name)

    return installed