HC-SR04 Ultrasonic Arduino Library is specifically for the HC-SR04 ultrasonic sensor. It features timing, metric conversion, and standard deviation methods, plus a few support methods. It is written in C++ to conserve the namespace. The conversion formula can be easily modified to optimize the accuracy of conversion at different distances for inches and centimeters. Multiple buffers of different lengths can be created for determining standard deviation.
Sunrise Sunset is a Python package that can determine the sunrise and sunset based on a given altitude zenith. It has two public methods. The first returns the sunrise and sunset in a tuple. The second returns True or False depending on whether the supplied date/time is during the night or day. The constructor takes three arguments, a date, latitude, and longitude. There is one keyword argument for changing the default zenith, which is set to "official". The zeniths are "official", "civil", "nautical", "amateur" (astronomical), and "astronomical". It does not rely on third party packages, but you may need something like pytz to create dates with timezone info.