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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 is_submodule_included(src, tgt):
 """Check that the tgt's submodule is included by src, if they belong to the same module."""

    if tgt is None or not hasattr(tgt, 'i_orig_module'):
        return True
    if (tgt.i_orig_module.keyword == 'submodule' and
        src.i_orig_module != tgt.i_orig_module and
        src.i_orig_module.i_modulename == tgt.i_orig_module.i_modulename):
        if src.i_orig_module.search_one('include',
                                        tgt.i_orig_module.arg) is None:
            return False
    return True