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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 _process_key(evt):
 """Helper to convert from wx keycode to vispy keycode"""

    key = evt.GetKeyCode()
    if key in KEYMAP:
        return KEYMAP[key], ''
    if 97 <= key <= 122:
        key -= 32
    if key >= 32 and key <= 127:
        return keys.Key(chr(key)), chr(key)
    else:
        return None, None