Create Assignment4.py

Author: Quarkblue

Assignments/Assignment4.py

@@ -0,0 +1,38 @@
+import os
+
+class ConfigkeyError(Exception):
+    def __init__(self,this,key):
+        self.key = key
+        self.keys = this.keys()
+        
+    def __str__(self):
+        return 'key "{0}" not found. Available keys: ({1})'.format(self.key,', '.join(self.keys))
+
+class ConfigDict(dict):
+    
+    def __init__(self,filename):
+        self._file = filename
+        if not os.path.isfile(self._file):
+            try:
+                open(self._file,'r+').close()
+            except IOError:
+                raise IOError('arg to ConfigDict must be a valid pathname')
+        with open(self._file) as file:
+            lines = file.readlines()
+            for line in lines:
+                line.rstrip()
+                key, value = line.split("=",1)
+                dict.__setitem__(self, key, value)
+                    
+    
+    def __setitem__(self, key, value):
+        dict.__setitem__(self, key, value)
+        with open(self._file,'w') as file:
+            for key,value in self.items():
+                file.write('{0}={1}\n'.format(key,value))
+                
+    def __getitem__(self, key):
+        if not key in self:
+            raise ConfigkeyError(self, key)
+        return dict.__getitem__(self, key)
+