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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 gen_submodule_names(package):
 """Walk package and yield names of all submodules :type package: package :param package: The package to get submodule names of :returns: Iterator that yields names of all submodules of ``package`` :rtype: Iterator that yields ``str`` """

    for importer, modname, ispkg in pkgutil.walk_packages(
        path=package.__path__,
        prefix=package.__name__ + '.',
            onerror=lambda x: None):
        yield modname