Add: Parser + test

src/ergogen_footprint_converter/converter.py

@@ -1,3 +1,8 @@
 class Converter:
-    def __init__(self):
-        None
+    input = ""
+
+    def __init__(self, input: str):
+        self.input = input
+
+    def convert(self) -> str:
+        return ""