How to create a Friday 13th detector

In the Gregorian calendar, Friday the 13th is considered the unluckiest day and is tied to misfortunate circumstances. Each year, Friday the 13th occurs one to three times.

Let us discover how to detect if a Friday 13th falls out in a particular month of a given year.

Code

import datetime
import calendar
def detect_Friday_13(year,month):
    #Get the thirteen day of the month
    day_13_of_the_month = datetime.date(year,month,13)
    print("The thirteenth day of month {} and year {} is a {}.".format(month,year,day_13_of_the_month.strftime("%A"))) 
    if day_13_of_the_month.weekday() == 4:
       return True
    return False
detect_Friday_13(year=2023,month=3)
detect_Friday_13(year=2024,month=12)

Explanation

Now, let us go through the code above:

  • Lines 1–2: We import the required Python libraries.

  • Line 4: We define a function aiming to check if the thirteenth day of a given year and month is a Friday.

  • Line 6: We get the date of the thirteenth day of the given year and month and store it in the variable day_13_of_the_month.

  • Line 7: We display a message showing the day name of the day_13_of_the_month variable using the method strftime.

  • Lines 8–10: We extract the day of the week as an integer value out of the day_13_of_the_month variable nd check if it is equal to 4 (Friday). If this is the case return True else return False.

  • Lines 12–13: We call the function detect_Friday_13 and check the output generated.

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