Modify custom_equation defaults and global calls

Updated default parameter values for custom_equation function and fixed global variable declaration.

Author: zeynepnur7

Week04/functions_zeynepnur_erten.py

@@ -2,7 +2,7 @@
 custom_power = lambda x=0,/, e=1 : x ** e
 
 
-def custom_equation(x: int , y: int , /, a:  int, b: int , * , c: int) -> float :
+def custom_equation(x: int = 0 , y: int = 0 , /, a: int = 1, b: int=1 , * , c: int = 1) -> float :
   """
    This function returns the result of an operation based on the specified base and exponent values.
 
@@ -18,7 +18,7 @@ def custom_equation(x: int , y: int , /, a:  int, b: int , * , c: int) -> float
 
 calls = 0
 def fn_w_counter()->(int, dict[str, int]):
-    global calls,
+    global calls
     calls += 1
     return calls, {__name__: calls }