Japanese Flag Drawing

Drawing a japanese flag with help of the symbols '*', '0', '#', ' ' (ASCII graphics with help of taxicab geometry).

Common requirements

• The input N shall be an integer even number
• The width of the inner area of the rectangle (excluding border) shall be 3 * N
• The height of the inner area of the rectangle (excluding border) shall be 2 * N
• The vertical distance between the circle and the border of the rectangle shall be N/2
• The horizontal distance between the circle and the border of the rectangle shall be N
• # symbol shall be used for rectangle border, * symbol shall be used for the circle border, o symbol shall be used for inner circle area
• The function shall return a string and use \n as line separators
• The function shall accept a single parameter N
• If the parameter is not a valid even integer number the ArgumentError exception shall be thrown
• The result of the task shall be provided a single python file named flag.py with a function named flag defined in it

Usage of the program

$ flag.py --number 4
##############
#            #
#            #
#     **     #
#    *00*    #
#    *00*    #
#     **     #
#            #
#            #
##############

The --number argument should be an even integer number.