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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 save_version_info(self, filename):
 """ Materialize the value of date into the build tag. Install build keys in a deterministic order to avoid arbitrary reordering on subsequent builds. """

        egg_info = collections.OrderedDict()
        # follow the order these keys would have been added
        # when PYTHONHASHSEED=0
        egg_info['tag_build'] = self.tags()
        egg_info['tag_date'] = 0
        edit_config(filename, dict(egg_info=egg_info))