




"""simple docstring"""







def      __snake_case (				_lowercase    ):


    """simple docstring"""







    return credit_card_number.startswith(('''34''', '''35''', '''37''', '''4''', '''5''', '''6''')    )





def      __snake_case (				_lowercase    ):


    """simple docstring"""







    UpperCamelCase              =	credit_card_number
    UpperCamelCase              =	0
    UpperCamelCase              =	len(lowercase__    ) - 2
    for i in range(lowercase__			,-1			,-2    ):
        #  double the value of every second digit
        UpperCamelCase              =	int(cc_number[i]    )
        digit *= 2
        # If doubling of a number results in a two digit number
        # i.e greater than 9(e.g., 6 × 2 = 12),
        # then add the digits of the product (e.g., 12: 1 + 2 = 3, 15: 1 + 5 = 6),
        # to get a single digit number.
        if digit > 9:
            digit %= 10
            digit += 1
        UpperCamelCase              =	cc_number[:i] + str(lowercase__    ) + cc_number[i + 1 :]
        total += digit

    # Sum up the remaining digits
    for i in range(len(lowercase__    ) - 1			,-1			,-2    ):
        total += int(cc_number[i]    )

    return total % 10 == 0





def      __snake_case (				_lowercase    ):


    """simple docstring"""







    UpperCamelCase              =	f'{credit_card_number} is an invalid credit card number because'
    if not credit_card_number.isdigit():
        print(f'{error_message} it has nonnumerical characters.'    )
        return False

    if not 13 <= len(lowercase__    ) <= 16:
        print(f'{error_message} of its length.'    )
        return False

    if not validate_initial_digits(lowercase__    ):
        print(f'{error_message} of its first two digits.'    )
        return False

    if not luhn_validation(lowercase__    ):
        print(f'{error_message} it fails the Luhn check.'    )
        return False

    print(f'{credit_card_number} is a valid credit card number.'    )
    return True


if __name__ == "__main__":
  import doctest

  doctest.testmod()
  validate_credit_card_number('4111111111111111')
  validate_credit_card_number('32323')


'''simple docstring'''

from __future__ import annotations

def 					__UpperCamelCase				(						lowercase__    :	float,       lowercase__    :	float,       lowercase__    :	float			):






     '''simple docstring'''





     if (voltage, current, resistance).count(0			) != 1:
          raise ValueError('One and only one argument must be 0'			)
     if resistance < 0:
          raise ValueError('Resistance cannot be negative'			)
     if voltage == 0:
          return {"voltage": float(current * resistance			)}
     elif current == 0:
          return {"current": voltage / resistance}
     elif resistance == 0:
          return {"resistance": voltage / current}
     else:
          raise ValueError('Exactly one argument must be 0'			)


if __name__ == "__main__":
       import doctest

       doctest.testmod()


