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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 venv():
 """Install venv + deps."""

    try:
        import virtualenv  # NOQA
    except ImportError:
        sh("%s -m pip install virtualenv" % PYTHON)
    if not os.path.isdir("venv"):
        sh("%s -m virtualenv venv" % PYTHON)
    sh("venv\\Scripts\\pip install -r %s" % (REQUIREMENTS_TXT))