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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 select_scheme(self, name):
 """Sets the install directories by applying the install schemes."""

        # it's the caller's problem if they supply a bad name!
        scheme = INSTALL_SCHEMES[name]
        for key in SCHEME_KEYS:
            attrname = 'install_' + key
            if getattr(self, attrname) is None:
                setattr(self, attrname, scheme[key])