rename variables using underscores

.gitignore

@@ -99,3 +99,5 @@ ENV/
 
 # mypy
 .mypy_cache/
+
+.vscode

algs4/bag.py

@@ -5,7 +5,7 @@
 % more tobe.txt
 to be or not to - be - - that - - - is
 
-% python stack < tobe.txt
+% python bag.py < tobe.txt
 to be or not to - be - - that - - - is
 """
 

algs4/stack.py

@@ -4,7 +4,7 @@
 % more tobe.txt 
 to be or not to - be - - that - - - is
 
-% python stack < tobe.txt
+% python stack.py < tobe.txt
 to be not that or be (2 left on stack)
 """
 

algs4/utils/linklist.py

@@ -1,8 +1,8 @@
 class Node:
 
-    def __init__(self, item, nextItem):
+    def __init__(self, item, next_node):
         self.item = item
-        self.next = nextItem
+        self.next = next_node
 
 
 class LinkIterator:

algs4/utils/st.py

@@ -1,9 +1,9 @@
 class Node:
 
-    def __init__(self, key, val, nextItem):
+    def __init__(self, key, val, next_node):
         self.key = key
         self.val = val
-        self.next = nextItem
+        self.next = next_node
 
 
 class STKeyIterator: