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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_children_of(self, component, kind=None):
 """ get to component labels of the children of a given component """


        structure, trace, item = self._get_structure_and_trace(component)
        item_kind, item_label = item.split(':')

        if isinstance(kind, str):
            kind = [kind]

        if item_kind not in ['orbit']:
            # return None
            return []
        else:
            items = self._get_by_trace(structure, trace[:-1]+[trace[-1]+1])
            # we want to ignore suborbits
            #return [str(ch.split(':')[-1]) for ch in items if isinstance(ch, unicode)]
            return [str(ch.split(':')[-1]) for ch in items if isinstance(ch, unicode) and (kind is None or ch.split(':')[0] in kind)]