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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_unhidden_ungenerated_python_files(directory: str) -> Iterable[str]: """Iterates through relevant python files within the given directory. Args: directory: The top-level directory to explore. Yields: File paths. """

    for dirpath, dirnames, filenames in os.walk(directory, topdown=True):
        if os.path.split(dirpath)[-1].startswith('.'):
            dirnames.clear()
            continue

        for filename in filenames:
            if filename.endswith('.py') and not filename.endswith('_pb2.py'):
                yield os.path.join(dirpath, filename)