<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def core_name(self):
 """Returns the name of the target ARM core. Args: self (JLink):
 the ``JLink`` instance Returns: The target core's name. """

        buf_size = self.MAX_BUF_SIZE
        buf = (ctypes.c_char * buf_size)()
        self._dll.JLINKARM_Core2CoreName(self.core_cpu(), buf, buf_size)
        return ctypes.string_at(buf).decode()