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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_usrgos_g_section(self, section=None):
 """Get usrgos in a requested section."""

        if section is None:
            section = self.hdrobj.secdflt
        if section is True:
            return self.usrgos
        # Get dict of sections and hdrgos actually used in grouping
        section2hdrgos = cx.OrderedDict(self.get_sections_2d())
        hdrgos_lst = section2hdrgos.get(section, None)
        if hdrgos_lst is not None:
            hdrgos_set = set(hdrgos_lst)
            hdrgos_u = hdrgos_set.intersection(self.hdrgo_is_usrgo)
            hdrgos_h = hdrgos_set.intersection(self.hdrgo2usrgos.keys())
            usrgos = set([u for h in hdrgos_h for u in self.hdrgo2usrgos.get(h)])
            usrgos |= hdrgos_u
            return usrgos
        return set()