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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_list_venvs(self):
 """Prints out and returns a list of known virtual environments. :rtype: list :return: list of virtual environments """

        self.logger.info('Listing known virtual environments ...')
        venvs = self.get_venvs()
        for venv in venvs:
            self.logger.info('Found `%s`' % venv)
        else:
            self.logger.info('No virtual environments found in `%s` directory.' % VENVS_DIRNAME)
        return venvs