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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 to_bytes(value):
 """Converts bytes, unicode, and C char arrays to bytes. Unicode strings are encoded to UTF-8. """

    if isinstance(value, text_type):
        return value.encode('utf-8')
    elif isinstance(value, ffi.CData):
        return ffi.string(value)
    elif isinstance(value, binary_type):
        return value
    else:
        raise ValueError('Value must be text, bytes, or char[]')