Removed update/insert/delete

I don't use them and AFAIK this module has no other users

relational/relation.py

@@ -371,72 +371,6 @@ class Relation(NamedTuple):
 
         return res
 
-    def update(self, expr: str, dic: dict) -> int:
-        '''
-        Updates certain values of a relation.
-
-        expr must be a valid Python expression that can contain field names.
-
-        This operation will change the relation itself instead of generating a new one,
-        updating all the tuples where expr evaluates as True.
-
-        Dic must be a dictionary that has the form "field name":"new value". Every kind of value
-        will be converted into a string.
-
-        Returns the number of affected rows.
-        '''
-        affected = self.selection(expr)
-        not_affected = self.difference(affected)
-
-        new_values = tuple(
-            zip(self.header.getAttributesId(dic.keys()), dic.values())
-        )
-
-        for i in set(affected.content):
-            li = list(i)
-
-            for column, value in new_values:
-                li[column] = value
-            not_affected.insert(li)
-
-        self.content = not_affected.content
-        return len(affected)
-
-    def insert(self, values: Union[list,tuple]) -> int:
-        '''
-        Inserts a tuple in the relation.
-        This function will not insert duplicate tuples.
-        All the values will be converted in string.
-        Will return the number of inserted rows.
-
-        Will fail if the tuple has the wrong amount of items.
-        '''
-
-        if len(self.header) != len(values):
-            raise Exception(
-                'Tuple has the wrong size. Expected %d, got %d' % (
-                    len(self.header),
-                    len(values)
-                )
-            )
-
-        prevlen = len(self.content)
-        self.content.add(tuple(map(Rstring, values)))
-        return len(self.content) - prevlen
-
-    def delete(self, expr: str) -> int:
-        '''
-        Delete, expr must be a valid Python expression; can contain field names.
-
-        This operation will change the relation itself instead of generating a new one,
-        deleting all the tuples where expr evaluates as True.
-
-        Returns the number of affected rows.'''
-
-        l = len(self.content)
-        self.content = self.difference(self.selection(expr)).content
-        return len(self.content) - l
-
 
 class Header(tuple):