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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 executeMethod(self, methodName, args):
 """Executes a method named ``methodName`` with the specified arguments. This method is called when the user executes a command as defined in the node spec. It provides a perfectly reasonble implementation of the command mechanism. As a sub-class developer you just need to implement a method for each command in the node spec. Note that due to the command mechanism only unnamed argument are supported. :param methodName: (string) the name of the method that correspond to a command in the spec. :param args: (list) of arguments that will be passed to the method """

    if not hasattr(self, methodName):
      raise Exception('Missing command method: ' + methodName)

    m = getattr(self, methodName)
    if not hasattr(m, '__call__'):
      raise Exception('Command: ' + methodName + ' must be callable')

    return m(*args)