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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 _pyxb_from_norm_perm_list(self, norm_perm_list):
 """Return an AccessPolicy PyXB representation of ``norm_perm_list``"""

        # Using accessPolicy() instead of AccessPolicy() and accessRule() instead of
        # AccessRule() gives PyXB the type information required for using this as a
        # root element.
        access_pyxb = d1_common.types.dataoneTypes.accessPolicy()
        for perm_str, subj_list in norm_perm_list:
            rule_pyxb = d1_common.types.dataoneTypes.accessRule()
            rule_pyxb.permission.append(perm_str)
            for subj_str in subj_list:
                rule_pyxb.subject.append(subj_str)
            access_pyxb.allow.append(rule_pyxb)
        if len(access_pyxb.allow):
            return access_pyxb