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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 _allowed_char(c):
 """ Returns whether the given unicode char is allowed in output """

    c = ord(c)
    if c < 0:
        return False
    if c < 128:
        return _ascii_allowed[c]
    # Genereally allow unicodes, TODO: check for unicode control characters
    # characters
    return True