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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 add_field(self, name, label, field_type, *args, **kwargs):
 """ Add the field to the internal configuration dictionary. """

        if name in self._dyn_fields:
            raise AttributeError('Field already added to the form.')
        else:
            self._dyn_fields[name] = {'label': label, 'type': field_type,
                                      'args': args, 'kwargs': kwargs}