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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 arg(name=None, **Config):
 # wraps the _arg decorator, in order to allow unnamed args r"""A decorator to configure an argument of a task. Config: * name (str):
 The name of the arg. When ommited the agument will be identified through the order of configuration. * desc (str):
 The description of the arg (optional). * type (type, CustomType, callable):
 The alias for the task (optional). Notes: * It always follows a @task or an @arg. """

  if name is not None: # allow name as a positional arg
    Config['name'] = name

  return lambda decorated: _arg(decorated, **Config)