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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 application_version_set(version):
 """Charm authors may trigger this command from any hook to output what version of the application is running. This could be a package version, for instance postgres version 9.5. It could also be a build number or version control revision identifier, for instance git sha 6fb7ba68. """


    cmd = ['application-version-set']
    cmd.append(version)
    try:
        subprocess.check_call(cmd)
    except OSError:
        log("Application Version: {}".format(version))