add logging and main function to fancymath

src/fancymath/__main__.py

@@ -0,0 +1,36 @@
+import logging
+
+root_logger = logging.getLogger()
+
+fmt = "%(asctime)s %(levelname)-8.8s [%(name)s:%(lineno)s] %(message)s"
+formatter = logging.Formatter(fmt)
+
+sh = logging.StreamHandler()
+sh.setFormatter(formatter)
+sh.setLevel(logging.INFO)
+
+fh = logging.FileHandler("fancymath.log")
+fh.setFormatter(formatter)
+fh.setLevel(logging.NOTSET)
+
+root_logger.addHandler(sh)
+root_logger.addHandler(fh)
+
+root_logger.setLevel(logging.NOTSET)
+
+logger = logging.getLogger(__name__)
+
+logger.info("Welcome to FancyMath, a silly library for demonstrations.")
+
+from fancymath.vector import Vector
+
+v1 = Vector(1,2,3)
+v2 = Vector(2,3,4)
+
+v3 = v1.dot(v2)
+
+logger.info(f"{v1=}")
+logger.info(f"{v2=}")
+logger.info(f"{v3=}")
+
+v4 = v2.dot([1,2,3])