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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 prepare(self, variables):
 """Initialize all steps in this recipe using their parameters. Args: variables (dict):
 A dictionary of global variable definitions that may be used to replace or augment the parameters given to each step. Returns: list of RecipeActionObject like instances: The list of instantiated steps that can be used to execute this recipe. """

        initializedsteps = []
        if variables is None:
            variables = dict()
        for step, params, _resources, _files in self.steps:
            new_params = _complete_parameters(params, variables)
            initializedsteps.append(step(new_params))
        return initializedsteps