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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 get_subclasses(modulepath, parent_class):
 """given a module return all the parent_class subclasses that are found in that module and any submodules. :param modulepath: string, a path like foo.bar.che :param parent_class: object, the class whose children you are looking for :returns: set, all the found child classes in modulepath of parent_class """

    if isinstance(modulepath, ModuleType):
        modules = get_modules(modulepath.__name__)
    else:
        modules = get_modules(modulepath)

    ret = set()
    for m in modules:
        cs = inspect.getmembers(m, lambda v: inspect.isclass(v) and issubclass(v, parent_class))
        for class_name, klass in cs:
            ret.add(klass)

    return ret