![]() Thanks to Tom Leys for that smart idea using a side-effect-less dict constructor for extend. """Create a new dictionary with a's properties extended by b, To remove the assignment, you could do it thus: def extend(a,b): EDIT: To add some additional information, here's something I've tried so far. tdefault(key, default) - Instance method return value of the given key, if it exists in the Otherwise, add the given key with the default value. Of course, you could simple note that a.extend(b) is nearly the same as b.update(a) a=b. If we added the following code in the middle of our original script we could see that after the addition, we still have 6 tuples. ![]() Then we take the two lists of tuples, add them together using the + operator. Each tuple holding one key-value pair from the dictionary. Remember that in the future you just want to remember why you did something and you won't care much if you spare some microseconds. Note that some languages call this method defaults or inject, as it can be thought of as a way of injecting b's values (which might be a set of default values) in to a dictionary without overwriting values that might already exist. We used the items method of the >dictionary object that returns a list of tuples. The answer in my opinion is no.Looping through key,values in a dict is already efficient and assigning columns with dfk v is more readable. a.update(b) overwrites a's values, and so isn't a good choice for extend. However, I want to point out that many times I have seen the extend method of mapping/set objects desire that in the syntax a.extend(b), a's values should NOT be overwritten by b's values. ![]() (Of course it does not make a copy of the dictionary to be added, but you can modify this behaviour be appending py () ). You can add an item to a dictionary or update the value of an existing item as follows. The code for the function is then incredibly simple: def addstudent (dictionarylist, studentdictionary): dictionarylist.append (studentdictionary) return dictionarylist. As others have mentioned, a.update(b) for some dicts a and b will achieve the result you've asked for in your question. Add or update an item in a dictionary by specifying a key.
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