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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 to_env_vars(self):
 """Environment variable representation of the training environment Returns: dict: an instance of dictionary """


        env = {
            'hosts': self.hosts, 'network_interface_name': self.network_interface_name,
            'hps': self.hyperparameters, 'user_entry_point': self.user_entry_point,
            'framework_params': self.additional_framework_parameters,
            'resource_config': self.resource_config, 'input_data_config': self.input_data_config,
            'output_data_dir': self.output_data_dir,
            'channels': sorted(self.channel_input_dirs.keys()),
            'current_host': self.current_host, 'module_name': self.module_name,
            'log_level': self.log_level,
            'framework_module': self.framework_module, 'input_dir': self.input_dir,
            'input_config_dir': self.input_config_dir, 'output_dir': self.output_dir,
            'num_cpus': self.num_cpus,
            'num_gpus': self.num_gpus, 'model_dir': self.model_dir, 'module_dir': self.module_dir,
            'training_env': dict(self), 'user_args': self.to_cmd_args(),
            'output_intermediate_dir': self.output_intermediate_dir
        }

        for name, path in self.channel_input_dirs.items():
            env['channel_%s' % name] = path

        for key, value in self.hyperparameters.items():
            env['hp_%s' % key] = value

        return _mapping.to_env_vars(env)