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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:
 async def i2c_read_data(self, address):
 """ This method retrieves cached i2c data to support a polling mode. :param address: I2C device address :returns: Last cached value read """

        if address in self.i2c_map:
            map_entry = self.i2c_map.get(address)
            data = map_entry.get('value')
            return data
        else:
            return None