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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 package_in_memory(cls, workflow_name, workflow_files):
 """ Generates wf packages from workflow diagrams. Args: workflow_name: Name of wf workflow_files: Diagram file. Returns: Workflow package (file like) object """

        s = StringIO()
        p = cls(s, workflow_name, meta_data=[])
        p.add_bpmn_files_by_glob(workflow_files)
        p.create_package()
        return s.getvalue()