group() {
	group() {
		hull() {
			multmatrix([[1, 0, 0, 15], [0, 1, 0, 10], [0, 0, 1, 0], [0, 0, 0, 1]]) {
				circle($fn = 0, $fa = 12, $fs = 2, r = 10);
			}
			difference() {
				circle($fn = 0, $fa = 12, $fs = 2, r = 10);
				circle($fn = 0, $fa = 12, $fs = 2, r = 5);
			}
		}
	}
	multmatrix([[1, 0, 0, 40], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 0, 1]]) {
		group() {
			hull() {
				multmatrix([[1, 0, 0, 15], [0, 1, 0, 10], [0, 0, 1, 0], [0, 0, 0, 1]]) {
					circle($fn = 0, $fa = 12, $fs = 2, r = 10);
				}
				circle($fn = 0, $fa = 12, $fs = 2, r = 10);
			}
		}
	}
	multmatrix([[1, 0, 0, 0], [0, 1, 0, -20], [0, 0, 1, 0], [0, 0, 0, 1]]) {
		group() {
			hull() {
				multmatrix([[1, 0, 0, 15], [0, 1, 0, 10], [0, 0, 1, 0], [0, 0, 0, 1]]) {
					square(size = [2, 2], center = false);
				}
				multmatrix([[1, 0, 0, 15], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 0, 1]]) {
					square(size = [2, 2], center = false);
				}
				square(size = [2, 2], center = false);
			}
		}
	}
	multmatrix([[1, 0, 0, 30], [0, 1, 0, -25], [0, 0, 1, 0], [0, 0, 0, 1]]) {
		group() {
			hull() {
				group() {
					group() {
						multmatrix([[1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 0, 1]]) {
							circle($fn = 0, $fa = 12, $fs = 2, r = 3);
						}
						multmatrix([[1, 0, 0, 0], [0, 1, 0, 10], [0, 0, 1, 0], [0, 0, 0, 1]]) {
							circle($fn = 0, $fa = 12, $fs = 2, r = 3);
						}
					}
					group() {
						multmatrix([[1, 0, 0, 10], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 0, 1]]) {
							circle($fn = 0, $fa = 12, $fs = 2, r = 3);
						}
						multmatrix([[1, 0, 0, 10], [0, 1, 0, 10], [0, 0, 1, 0], [0, 0, 0, 1]]) {
							circle($fn = 0, $fa = 12, $fs = 2, r = 3);
						}
					}
				}
			}
		}
	}
	group() {
		hull() {
			square(size = [0, 0], center = false);
			circle($fn = 0, $fa = 12, $fs = 2, r = 0);
		}
	}
}