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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_version(file_path):
 """ Find the version of pygccxml. Used by setup.py and the sphinx's conf.py. Inspired by https://packaging.python.org/single_source_version/ Args: file_path (str):
 path to the file containing the version. """


    with io.open(
            os.path.join(
                os.path.dirname(__file__),
                os.path.normpath(file_path)),
            encoding="utf8") as fp:
        content = fp.read()

    version_match = re.search(r"^__version__ = ['\"]([^'\"]*)['\"]",
                              content, re.M)
    if version_match:
        return version_match.group(1)
    raise RuntimeError("Unable to find version string.")