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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 parse(self, line, namespace=None):
 """Parses a line into a dictionary of arguments, expanding meta-variables from a namespace. """

    try:
      if namespace is None:
        ipy = IPython.get_ipython()
        namespace = ipy.user_ns
      args = CommandParser.create_args(line, namespace)
      return self.parse_args(args)
    except Exception as e:
      print(str(e))
      return None