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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 _get_spec(self, spec_file):
 """Get json specification from package data."""

        spec_file_path = os.path.join(
            pkg_resources.
            resource_filename(
                'reana_commons',
                'openapi_specifications'),
            spec_file)

        with open(spec_file_path) as f:
            json_spec = json.load(f)
        return json_spec