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Convert a python dict to a string and back

The json module is a good solution here. It has the advantages over pickle that it only produces plain text output, and is cross-platform and cross-version.

append multiple values for one key in a dictionary [duplicate]

If I can rephrase your question, what you want is a dictionary with the years as keys and an array for each year containing a list of values associated with that year, right? Here’s how I’d do it: What you should end up with in years_dict is a dictionary that looks like the following: In … Read more

How can I remove a key from a Python dictionary?

To delete a key regardless of whether it is in the dictionary, use the two-argument form of dict.pop(): This will return my_dict[key] if key exists in the dictionary, and None otherwise. If the second parameter is not specified (i.e. my_dict.pop(‘key’)) and key does not exist, a KeyError is raised. To delete a key that is guaranteed to exist, you can also use: This will raise a KeyError if the … Read more

Are dictionaries ordered in Python 3.6+?

Are dictionaries ordered in Python 3.6+? They are insertion ordered[1]. As of Python 3.6, for the CPython implementation of Python, dictionaries remember the order of items inserted. This is considered an implementation detail in Python 3.6; you need to use OrderedDict if you want insertion ordering that’s guaranteed across other implementations of Python (and other ordered behavior[1]). As of Python 3.7, this … Read more

How can I get dictionary key as variable directly in Python (not by searching from value)?

You should iterate over keys with:

Error: ” ‘dict’ object has no attribute ‘iteritems’ “

As you are in python3 , use dict.items() instead of dict.iteritems() iteritems() was removed in python3, so you can’t use this method anymore. Take a look at Python 3.0 Wiki Built-in Changes section, where it is stated: Removed dict.iteritems(), dict.iterkeys(), and dict.itervalues(). Instead: use dict.items(), dict.keys(), and dict.values() respectively.

Getting key with maximum value in dictionary?

You can use operator.itemgetter for that: And instead of building a new list in memory use stats.iteritems(). The key parameter to the max() function is a function that computes a key that is used to determine how to rank items. Please note that if you were to have another key-value pair ‘d’: 3000 that this method will only return one of the two even though they … Read more