cimal place and may
        require the addition of either one or two trailing zeros.

        The operation is not affected by the context.

        >>> ExtendedContext.to_eng_string(Decimal('123E+1'))
        '1.23E+3'
        >>> ExtendedContext.to_eng_string(Decimal('123E+3'))
        '123E+3'
        >>> ExtendedContext.to_eng_string(Decimal('123E-10'))
        '12.3E-9'
        >>> ExtendedContext.to_eng_string(Decimal('-123E-12'))
        '-123E-12'
        >>> ExtendedContext.to_eng_string(Decimal('7E-7'))
        '700E-9'
        >>> ExtendedContext.to_eng_string(Decimal('7E+1'))
        '70'
        >>> ExtendedContext.to_eng_string(Decimal('0E+1'))
        '0.00E+3'

        Tr§