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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_by_root_package(where):
 """Better than excluding everything that is not needed, collect only what is needed. """

    root_package = os.path.basename(where)
    packages = [ "%s.%s" % (root_package, sub_package)
                 for sub_package in find_packages(where)]
    packages.insert(0, root_package)
    return packages