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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 from_configuration(cls, env_name, config_name='default'):
 """ Environment factory from name and configuration strings. :param str env_name: the name string of the environment :param str config_name: the configuration string for env_name Environment name strings are available using:: from explauto.environment import environments print environments.keys() This will return the available environment names, something like:: '['npendulum', 'pendulum', 'simple_arm']' Once you have choose an environment, e.g. 'simple_arm', corresponding available configurations are available using:: env_cls, env_configs, _ = environments['simple_arm'] print env_configs.keys() This will return the available configuration names for the 'simple_arm' environment, something like:: '['mid_dimensional', 'default', 'high_dim_high_s_range', 'low_dimensional', 'high_dimensional']' Once you have choose a configuration, for example the 'mid_dimensional' one, you can contruct the environment using:: from explauto import Environment my_environment = Environment.from_configuration('simple_arm', 'mid_dimensional') Or, in an equivalent manner:: my_environment = env_cls(**env_configs['mid_dimensional']) """

        env_cls, env_configs, _ = environments[env_name]
        return env_cls(**env_configs[config_name])