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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 export_as_file(self, filepath, hyperparameters):
 """Generates a Python file with the importable base learner set to ``hyperparameters`` This function generates a Python file in the specified file path that contains the base learner as an importable variable stored in ``base_learner``. The base learner will be set to the appropriate hyperparameters through ``set_params``. Args: filepath (str, unicode):
 File path to save file in hyperparameters (dict):
 Dictionary to use for ``set_params`` """

        if not filepath.endswith('.py'):
            filepath += '.py'

        file_contents = ''
        file_contents += self.source
        file_contents += '\n\nbase_learner.set_params(**{})\n'.format(hyperparameters)
        file_contents += '\nmeta_feature_generator = "{}"\n'.format(self.meta_feature_generator)
        with open(filepath, 'wb') as f:
            f.write(file_contents.encode('utf8'))