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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 set_installed_version(vcs, version):
 """Set the installed version for this project. Args: vcs (easyci.vcs.base.Vcs) version (str) """

    version_path = _get_version_path(vcs)
    with open(version_path, 'w') as f:
        f.write(version)