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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 __add_types(self, raw_conf):
 """ Convert to int, boolean, list, None types config items """


        typed_conf = {}

        for s in raw_conf.keys():
            typed_conf[s] = {}
            for option in raw_conf[s]:
                val = raw_conf[s][option]
                if len(val) > 1 and (val[0] == '"' and val[-1] == '"'):
                    # It is a string
                    typed_conf[s][option] = val[1:-1]
                # Check list
                elif len(val) > 1 and (val[0] == '[' and val[-1] == ']'):
                    # List value
                    typed_conf[s][option] = val[1:-1].replace(' ', '').split(',')
                # Check boolean
                elif val.lower() in ['true', 'false']:
                    typed_conf[s][option] = True if val.lower() == 'true' else False
                # Check None
                elif val.lower() is 'none':
                    typed_conf[s][option] = None
                else:
                    try:
                        # Check int
                        typed_conf[s][option] = int(val)
                    except ValueError:
                        # Is a string
                        typed_conf[s][option] = val
        return typed_conf