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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 op_bootstrap(self):
 """Bootstraps django-dev by creating required directory structure."""

        self.logger.info('Bootstrapping django-dev directory structure in current directory ...')
        self.make_venv(DJANGO_DEFAULT_VERSION)
        venv_path = self.make_venv('1.6.5')
        self.venv_install('south==1.0.1', venv_path)
        apps_dir = self.make_apps_dir()
        self.logger.info('Now you may symlink (ln -s) your apps '
                         '(and other apps that you apps depend upon) into %s' % apps_dir)