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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 hvenvup(package, directory):
 """ Install a new version of a package in the hitch venv. """

    pip = Command(DIR.gen.joinpath("hvenv", "bin", "pip"))
    pip("uninstall", package, "-y").run()
    pip("install", DIR.project.joinpath(directory).abspath()).run()