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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_version(dunder_file):
 """Returns a version string for the current package, derived either from git or from a .version file. This function is expected to run in two contexts. In a development context, where .git/ exists, the version is pulled from git tags. Using the BuildPyCommand and SDistCommand classes for cmdclass in setup.py will write a .version file into any dist. In an installed context, the .version file written at dist build time is the source of version information. """

    path = abspath(expanduser(dirname(dunder_file)))
    try:
        return _get_version_from_version_file(path) or _get_version_from_git_tag(path)
    except CalledProcessError as e:
        log.warn(repr(e))
        return None
    except Exception as e:
        log.exception(e)
        return None