'Builds and installs the package.  It must have been fetched already.
:param install_dir - The package installation directory.  If it does
not exist it will be created.'

def build_and_install(self, install_dir):

    if (not self.verified_package):
        raise Error(('Must    call    fetch()    first.        -    %s' % self.name))
    self._check_os_requirements()
    return self._build_and_install(install_dir)
