utils + parallel resistors calculator

utils.py

@@ -0,0 +1,27 @@
+#!/bin/python
+import re
+
+def parse_resistors(raw_input):
+    values = []
+    tokens = raw_input.replace(',', ' ').split()
+
+    for token in tokens:
+        match = re.fullmatch(r'([0-9]*\.?[0-9]+)\s*([KM]?)', token)
+        if not match:
+            raise ValueError(f"Invalid component value '{token}'")
+
+        number = float(match.group(1))
+        if number <= 0:
+            raise ValueError(f"Invalid component value '{token}' (must be positive)")
+
+        suffix = match.group(2)
+        if suffix == 'K':
+            multiplier = 1e3
+        elif suffix == 'M':
+            multiplier = 1e6
+        else:
+            multiplier = 1.0
+
+        values.append(number * multiplier)
+
+    return values