docs: def get_config(config_schema, env=None):
      """Parse config from the environment against a given schema
  
      Args:
          config_schema:
              A dictionary mapping keys in the environment to envpy Schema
              objects describing the expected value.
          env:
              An optional dictionary used to override the environment rather
              than getting it from the os.
  
      Returns:
          A dictionary which maps the values pulled from the environment and
          parsed against the given schema.
  
      Raises:
          MissingConfigError:
              A value in the schema with no default could not be found in the
              environment.
          ParsingError:
              A value was found in the environment but could not be parsed into
              the given value type.
      """
      if env is None:
          env = os.environ
  
      return parser.parse_env(
          config_schema,
          env,
      )