Define a period

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How many working days in year 1971?

Here is the detail of the calculation:

Because 1971 is not a leap year, it has 365 days.

Let's remove 52 saturdays and 52 sundays. It remains 261 days.

Now, let's remove 7 public holidays that do not fall during a weekend and we obtain 254 working days in 1971.

Here is the list of these 7 public holidays:

1. Solenidade da Santa Mãe de Deus : Friday, 1 January, 1971
2. Sexta-Feira Santa : Friday, 9 April, 1971
3. Corpo de Deus : Thursday, 10 June, 1971
4. Implantação da República : Tuesday, 5 October, 1971
5. Todos os Santos : Monday, 1 November, 1971
6. Restauração da Independência : Wednesday, 1 December, 1971
7. Dia da Imaculada Conceição : Wednesday, 8 December, 1971

And here are the 5 public holidays falling on a weekend:

1. Páscoa : Sunday, 11 April, 1971
2. Dia da Liberdade : Sunday, 25 April, 1971
3. Dia do Trabalhador : Saturday, 1 May, 1971
4. Assunção de Nossa Senhora : Sunday, 15 August, 1971
5. Natal : Saturday, 25 December, 1971