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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 find(value):
 """ returns a dictionary of rdfclasses based on the a lowercase search args: value: the value to search by """

        value = str(value).lower()
        rtn_dict = RegistryDictionary()
        for attr in dir(MODULE.rdfclass):
            if value in attr.lower():
                try:
                    item = getattr(MODULE.rdfclass, attr)
                    if issubclass(item, RdfClassBase):
                        rtn_dict[attr] = item
                except TypeError:
                    pass
        return rtn_dict