 
 <prompt> Wetin be di konvenshon wey dem dey follow wey one old case don set example? Based on di previous question, write one context wey get di answer. E fit be 1 - 20 sentences. Context: <response>: Federal law dey start with di Constitution, wey give Congress power to make laws for certain limited purposes like regulating interstate commerce. Di United States Code na di official compilation and codification of di general and permanent federal laws. Many laws give executive branch agencies power to create regulations, wey dey publish for di Federal Register and codified into di Code of Federal Regulations. Regulations generally also get power of law under di Chevron doctrine. Many lawsuits dey based on di meaning of a federal law or regulation, and judicial interpretations of such meaning get legal force under di principle of stare decisis. 