reformat with black and fix eror when "get" method

src/sqliteshelve/__init__.py

@@ -1,93 +1,102 @@
-#sqliteshelve module
-import  pickle, sqlite3, os
+# sqliteshelve module
+import pickle
+import sqlite3
+
 
 class Shelf(object):
-   """ Hackified Shelf class with sqlite3 """
-   def __init__(self,dbpath):
-      """ Opens or creates an existing sqlite3_shelf"""
-
-      self.db =  sqlite3.connect(dbpath)
-      #create shelf table if it doesn't already exist
-      cursor = self.db.cursor()
-      cursor.execute("select * from sqlite_master where type = 'table' and tbl_name = 'shelf'")
-      rows = cursor.fetchall()
-      if len(rows) == 0:
-          cursor.execute("create table shelf (id integer primary key autoincrement, key_str text, value_str text, unique(key_str))")
-      cursor.close()
-
-   def __setitem__(self,key,value):
-      """ Sets an entry for key to value using pickling """
-      pdata = pickle.dumps(value,pickle.HIGHEST_PROTOCOL)
-      curr = self.db.cursor()
-      curr.execute("insert or replace into shelf (key_str,value_str) values (:key,:value)",{ 'key' : key, 'value' : sqlite3.Binary(pdata)})
-      curr.close()
-
-   def get(self,key,default_value):
-      """ Returns an entry for key """    
-      curr = self.db.cursor()
-      curr.execute("select value_str from shelf where key_str = :key",{'key' : key})
-      result = curr.fetchone()
-      curr.close()
-      if result:
-         return pickle.loads(str(result[0]))
-      else:
-         return default_value
-
-   def __getitem__(self,key):
-      """ Returns an entry for key """    
-      curr = self.db.cursor()
-      curr.execute("select value_str from shelf where key_str = :key",{'key' : key})
-      result = curr.fetchone()
-      curr.close()
-      if result:
-         return pickle.loads(result[0])
-      else:
-         raise(KeyError, "Key: %s does not exist." % key)
-
-   def keys(self):
-      """ Returns list of keys """
-      curr = self.db.cursor()
-      curr.execute('select key_str from shelf')
-      keylist = [ row[0] for row in curr ]
-      curr.close()
-      return keylist
-
-   def __contains__(self,key):
-       """
-          implements in operator
-          if <key> in db
-       """
-       return key in self.keys()
-
-   def __iter__(self):
-       return iter(self.keys())
-
-
-   def __len__(self):
-      """ Returns number of entries in shelf """
-      return len(self.keys())
-
-   def __delitem__(self,key):
-      """ Deletes an existing item. """
-      curr = self.db.cursor()
-      curr.execute("delete from shelf where key_str = '%s'" % key)
-      curr.close()
-
-   def close(self):
-      """
+    """Hackified Shelf class with sqlite3"""
+
+    def __init__(self, dbpath):
+        """Opens or creates an existing sqlite3_shelf"""
+
+        self.db = sqlite3.connect(dbpath)
+        # create shelf table if it doesn't already exist
+        cursor = self.db.cursor()
+        cursor.execute(
+            "select * from sqlite_master where type = 'table' and tbl_name = 'shelf'"
+        )
+        rows = cursor.fetchall()
+        if len(rows) == 0:
+            cursor.execute(
+                "create table shelf (id integer primary key autoincrement, key_str text, value_str text, unique(key_str))"
+            )
+        cursor.close()
+
+    def __setitem__(self, key, value):
+        """Sets an entry for key to value using pickling"""
+        pdata = pickle.dumps(value, pickle.HIGHEST_PROTOCOL)
+        curr = self.db.cursor()
+        curr.execute(
+            "insert or replace into shelf (key_str,value_str) values (:key,:value)",
+            {"key": key, "value": sqlite3.Binary(pdata)},
+        )
+        curr.close()
+
+    def get(self, key, default_value):
+        """Returns an entry for key"""
+        curr = self.db.cursor()
+        curr.execute("select value_str from shelf where key_str = :key", {"key": key})
+        result = curr.fetchone()
+        curr.close()
+        if result:
+            return pickle.loads(result[0])
+        else:
+            return default_value
+
+    def __getitem__(self, key):
+        """Returns an entry for key"""
+        curr = self.db.cursor()
+        curr.execute("select value_str from shelf where key_str = :key", {"key": key})
+        result = curr.fetchone()
+        curr.close()
+        if result:
+            return pickle.loads(result[0])
+        else:
+            raise (KeyError, "Key: %s does not exist." % key)
+
+    def keys(self):
+        """Returns list of keys"""
+        curr = self.db.cursor()
+        curr.execute("select key_str from shelf")
+        keylist = [row[0] for row in curr]
+        curr.close()
+        return keylist
+
+    def __contains__(self, key):
+        """
+        implements in operator
+        if <key> in db
+        """
+        return key in self.keys()
+
+    def __iter__(self):
+        return iter(self.keys())
+
+    def __len__(self):
+        """Returns number of entries in shelf"""
+        return len(self.keys())
+
+    def __delitem__(self, key):
+        """Deletes an existing item."""
+        curr = self.db.cursor()
+        curr.execute("delete from shelf where key_str = '%s'" % key)
+        curr.close()
+
+    def close(self):
+        """
         Closes database and commits changes
-      """
-      self.db.commit()
+        """
+        self.db.commit()
+        self.db.close()
 
 
 def open(dbpath):
-    """ Creates and returns a Shelf object """
+    """Creates and returns a Shelf object"""
     return Shelf(dbpath)
 
 
 def close(db):
     """
-      commits changes to the database
+    commits changes to the database
     """
     db.close()
-