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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 install_json_output_variables(self, ij=None):
 """Return install.json output variables in a dict with name param as key. Args: ij (dict, optional):
 Defaults to None. The install.json contents. Returns: dict: A dictionary containing the install.json output variables with name as key. """

        if self._install_json_output_variables is None or ij is not None:
            self._install_json_output_variables = {}
            # TODO: currently there is no support for projects with multiple install.json files.
            if ij is None:
                ij = self.install_json
            for p in ij.get('playbook', {}).get('outputVariables') or []:
                self._install_json_output_variables.setdefault(p.get('name'), []).append(p)
        return self._install_json_output_variables