<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def received_raw(self):
 """ Return a list of all received headers in raw format """

        output = []
        for i in self.message.get_all("received", []):
            output.append(decode_header_part(i))
        return output