hourglass.py

'''
Elegant hourglass pattern generator.
'''

import itertools

def hourglass(n: int, char: str = "*") -> str:
    '''
    Generate an hourglass pattern.

    Args:
        n: Number of rows for the widest part
        char: Character to use for the pattern

    Returns:
        The hourglass pattern as a string

    Example (n=6):
        * * * * * *
         * * * * *
          * * * *
           * * *
            * *
             *
            * *
           * * *
          * * * *
         * * * * *
        * * * * * *
    '''
    rows = itertools.chain(range(n, 0, -1), range(2, n + 1))

    return "\n".join(f"{' ' * (n - i)}{f'{char} ' * i}".rstrip() for i in rows)


if __name__ == "__main__":
    row = int(input("Enter the number of rows: "))

    print(hourglass(row))