    def __init__(self, screen, x, y, diameter, life_time):
        """
        :param screen: The Screen being used for this particle system.
        :param x: The x position of the origin of the explosion.
        :param y: The y position of the origin of the explosion.
        :param diameter: The diameter of the explosion.
        :param life_time: The life time of this particle system.
        """
        super().__init__(
            screen, x, y, 50, self._next_particle, life_time, life_time)
        self._particles = None
        self._diameter = diameter
:param screen: The Screen being used for this particle system.
:param x: The x position of the origin of the explosion.
:param y: The y position of the origin of the explosion.
:param diameter: The diameter of the explosion.
:param life_time: The life time of this particle system.
asciimatics/particles.py