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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 ReinstallInstance(r, instance, os=None, no_startup=False, osparams=None):
 """ Reinstalls an instance. @type instance: str @param instance: The instance to reinstall @type os: str or None @param os: The operating system to reinstall. If None, the instance's current operating system will be installed again @type no_startup: bool @param no_startup: Whether to start the instance automatically """


    if INST_REINSTALL_REQV1 in r.features:
        body = {
            "start": not no_startup,
        }
        if os is not None:
            body["os"] = os
        if osparams is not None:
            body["osparams"] = osparams
        return r.request("post", "/2/instances/%s/reinstall" % instance,
                         content=body)

    # Use old request format
    if osparams:
        raise GanetiApiError("Server does not support specifying OS"
                             " parameters for instance reinstallation")

    query = {
        "nostartup": no_startup,
    }

    if os:
        query["os"] = os

    return r.request("post", "/2/instances/%s/reinstall" % instance,
                     query=query)