Fix linter issues

Author: lpozo

python-magic-methods/number.py

@@ -3,7 +3,7 @@ def __init__(self, value):
         self.value = value
 
     def __add__(self, other):
-        print(f"__add__ called")
+        print("__add__ called")
         if isinstance(other, Number):
             return Number(self.value + other.value)
         elif isinstance(other, int | float):
@@ -12,11 +12,11 @@ def __add__(self, other):
             raise TypeError("unsupported operand type for +")
 
     def __radd__(self, other):
-        print(f"__radd__ called")
+        print("__radd__ called")
         return self.__add__(other)
 
     def __iadd__(self, other):
-        print(f"__iadd__ called")
+        print("__iadd__ called")
         return self.__add__(other)
 
     def __str__(self):

python-magic-methods/storage.py

@@ -7,7 +7,7 @@ def __new__(cls, value, unit):
     def __add__(self, other):
         if not isinstance(other, type(self)):
             raise TypeError(
-                f"unsupported operand for +: "
+                "unsupported operand for +: "
                 f"'{type(self).__name__}' and '{type(other).__name__}'"
             )
         if not self.unit == other.unit:
@@ -20,7 +20,7 @@ def __add__(self, other):
     def __sub__(self, other):
         if not isinstance(other, type(self)):
             raise TypeError(
-                f"unsupported operand for -: "
+                "unsupported operand for -: "
                 f"'{type(self).__name__}' and '{type(other).__name__}'"
             )
         if not self.unit == other.unit: