<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def check_note(note, chord):
 """ Return True if the note is valid. :param str note: note to check its validity :param str chord: the chord which includes the note :rtype: bool """

    if note not in NOTE_VAL_DICT:
        raise ValueError("Invalid chord {}: Unknown note {}".format(chord, note))
    return True