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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 parse_value(value, allow_spaces=True, unquote=default_unquote):
    "Process a cookie value"
    if value is None:
        return None
    value = strip_spaces_and_quotes(value)
    value = parse_string(value, unquote=unquote)
    if not allow_spaces:
        assert ' ' not in value
    return value