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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 install_gitflow():
 """Install git-flow if not found"""

    if not run('which git-flow', hide=True, warn=True).ok:
        run('wget --no-check-certificate -q -O /tmp/gitflow-installer.sh  https://raw.github.com/petervanderdoes/gitflow/develop/contrib/gitflow-installer.sh')
        run('sudo bash /tmp/gitflow-installer.sh install stable')
        run('rm /tmp/gitflow-installer.sh')