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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 list_env(self, saltenv='base'):
        '''
        Return a list of the files in the file server's specified environment
        '''
        load = {'saltenv': saltenv,
                'cmd': '_file_list'}
        return salt.utils.data.decode(self.channel.send(load)) if six.PY2 \
            else self.channel.send(load)