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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_schema_type(cls, schema):
 """ Get schema type for the argument :param schema: Schema to analyze :return: COMPILED_TYPE constant :rtype: str|None """

        schema_type = type(schema)

        # Marker
        if issubclass(schema_type, markers.Marker):
            return const.COMPILED_TYPE.MARKER
        # Marker Type
        elif issubclass(schema_type, six.class_types) and issubclass(schema, markers.Marker):
            return const.COMPILED_TYPE.MARKER
        # CompiledSchema
        elif isinstance(schema, CompiledSchema):
            return const.COMPILED_TYPE.SCHEMA
        else:
            return primitive_type(schema)