from datetime import date

calculations = ['1.0 km = 1000.0 m', '500.0 m = 50000.0 cm',
                '2.5 km = 2500000.0 mm', '100.0 cm = 1.0 m',
                '250.0 mm = 25.0 cm']

# ***** Get current date for heading and filename ****
today = date.today()

# Get day, month and year as individual strings
day = today.strftime("%d")
month = today.strftime("%m")
year = today.strftime("%Y")

file_name = f"distances_{day}_{month}_{year}"
write_to = f"{file_name}.txt"

with open(write_to, 'w') as text_file:

    text_file.write("***** Distance Calculations *****\n")
    text_file.write(f"Generated: {day}/{month}/{year}\n\n")
    text_file.write("Here is your calculation history (oldest to newest)...\n")

    # write each item to file
    for item in calculations:
        text_file.write(item)
        text_file.write("\n")