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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 to_struct(cls, name=None):
 """ Convert the TreeModel into a compiled C struct """

        if name is None:
            name = cls.__name__
        basic_attrs = dict([(attr_name, value)
                            for attr_name, value in cls.get_attrs()
                            if isinstance(value, Column)])
        if not basic_attrs:
            return None
        src = 'struct {0} {{'.format(name)
        for attr_name, value in basic_attrs.items():
            src += '{0} {1};'.format(value.type.typename, attr_name)
        src += '};'
        if ROOT.gROOT.ProcessLine(src) != 0:
            return None
        return getattr(ROOT, name, None)