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1. Top results related to how do dictionaries work in python?

   • How do modules work in Python?

     Top Answer

     Answered Aug 07, 2013 · 4 votes

     When you import requests file __init__.pyis executed, if you examine that file in your case, you will find this line:

     from .api import request, get, head, post, patch, put, delete, options-

     Which means that from api.py you are importing get() function:

     def get(url, **kwargs): kwargs.setdefault('allow_redirects', True) return request('get', url, **kwargs)-

     And as you can see it calls request function from api.py that looks like:

     def request(method, url, **kwargs): session = sessions.Session() return session.request(method=method, url=url, **kwargs)-

     That creates an object Session defined inside session.py, then calls its method request. This method will call method send() which returns a Responseobject which is defined in the class Response inside models.py (I copy the first lines):

     class Response(object): def __init__(self): super(Response, self).__init__()- self._content = False self._content_consumed = False #: Integer Code of responded HTTP Status. self.status_code = None...

     Here is where status_code is defined, so when you invoke r = requests.get("http://www.google.com") you are retrieving this object and then you can access to status_code

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   • How do you append dictionaries to dictionaries in Python 3?

     Top Answer

     Answered Jun 02, 2014 · 7 votes

     Simply assign the key-value pair to the existing dict, specifying the new key as the subscript and the new value as the right-hand-side of the assignment:

     parent_dictionary['Dict3'] = {'a':'7', 'b': 8, 'c': 9}-

     Edit for the updated question: To merge two dicts, use the update method. For example, to add all keys from mother_dictionary to father_dictionary, use:

     father_dictionary.update(mother_dictionary)-

     To add a single key (and your question still doesn't make it clear if you need to add a single key or all keys), again make use of assignment:

     father_dictionary['Dict3'] = mother_dictionary['Dict3']-

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     2/5

   • How do nested functions work in Python?

     Top Answer

     Answered Jan 05, 2010 · 33 votes

     You can see it as all the variables originating in the parent function being replaced by their actual value inside the child function. This way, there is no need to keep track of the scope of the parent function to make the child function run correctly.

     See it as "dynamically creating a function".

     def maker(n): def action(x): return x ** n return actionf = maker(2)--> def action(x):--> return x ** 2

     This is basic behavior in python, it does the same with multiple assignments.

     a = 1b = 2a, b = b, a

     Python reads this as

     a, b = 2, 1-

     It basically inserts the values before doing anything with them.

     Other Answers

     Answered May 23, 2017 · 40 votes

     You are basically creating a closure.

     In computer science, a closure is a first-class function with free variables that are bound in the lexical environment. Such a function is said to be "closed over" its free variables.

     Related reading: Closures: why are they so useful?

     A closure is simply a more convenient way to give a function access to local state.

     From http://docs.python.org/reference/compound_stmts.html:

     Programmer’s note: Functions are first-class objects. A 'def' form executed inside a function definition defines a local function that can be returned or passed around. Free variables used in the nested function can access the local variables of the function containing the def. See section Naming and binding for details.

     Other Answers

     Answered Jan 25, 2010 · 15 votes

     You are defining TWO functions. When you call

     f = maker(2)-

     you're defining a function that returns twice the number, so

     f(2) --> 4f(3) --> 6

     Then, you define ANOTHER DIFFERENT FUNCTION

     g = maker(3)-

     that return three times the number

     g(3) ---> 9-

     But they are TWO different functions, it's not the same function referenced, each one it's a independent one. Even in the scope inside the function 'maker' are called the same, is't not the same function, each time you call maker() you're defining a different function. It's like a local variable, each time you call the function takes the same name, but can contain different values. In this case, the variable 'action' contains a function (which can be different)

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     3/5

   • How do bit masks work in Python?

     Top Answer

     Answered Jul 07, 2016 · 5 votes

     Computers represent integers with bits. This is a binary representation of a number (that is, using base 2). The only numbers in binary are 0 and 1, or "off" and "on". If you are not familiar with binary, you should read up on it, but basically you count in binary like this:

     0000000100100011010001010110

     and so on... each column can be represented by 2^n starting with 0. So the number 0101 = 2^3*0+2^2*1+2^1*0+2^0*1 = 5. Now when you "bit mask" something, you are basically just looking at the bits of value to you. In your case, you are only looking at the "2^3" bit. This is easily done by simply multiplying each bit with the corresponding bit in the mask. This can be useful for a lot of things. Sometimes we assign meaning to each bit and telling whether it is on or off is very important.

     In your example. If we passed in 13, this would happen:

     13 means 1101 in computer speak1101 mask with 1000. Work on each bit individually:1 * 1 = 11 * 0 = 00 * 0 = 01 * 0 = 0checker = 1000 which means 8.8 > 0 so return on.

     An example returning false with 5:

     5 means 0101 in computer speak0101 mask with 1000. Work on each bit individually:0 * 1 = 01 * 0 = 00 * 0 = 01 * 0 = 0checker = 0000 which means 0.0 is not > 0 so return off.

     Hope this helps. You should be able to find extensive information about this stuff on the google machine.

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     4/5

   • How do function arguments work in python?

     Top Answer

     Answered Jul 16, 2016 · 1 votes

     Function arguments are positional variables. You need to call the function and pass it the variables in order for it to work.

     Variables passed to a function are local, only usable in the function. You want to either change a global variable or return from that function.

     What your code is doing is passing unassigned variable names num1, op, num2 to a function.

     Read more here: http://www.tutorialspoint.com/python/python_functions.htm

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     5/5

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2. People also ask

   What is a dictionary in Python?

   • Dictionaries in Python is a data structure, used to store values in key:value format. This makes it different from lists, tuples, and arrays as in a dictionary each key has an associated value. Note: As of Python version 3.7, dictionaries are ordered and can not contain duplicate keys. How to Create a Dictionary

   Dictionaries in Python - GeeksforGeeks

   www.geeksforgeeks.org/python-dictionary/

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   What methods apply to dictionaries in Python?

   • The following is an overview of methods that apply to dictionaries: Clears a dictionary. Returns the value for a key if it exists in the dictionary. The Python dictionary .get() method provides a convenient way of getting the value of a key from a dictionary without checking ahead of time whether the key exists, and without raising an error.

   Dictionaries in Python – Real Python

   realpython.com/python-dicts/

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   How do you access a dictionary in Python?

   • Because Python dictionaries aren’t a sequence data type, we can’t simply access, say, the first item. In order to access a particular value in a Python dictionary, we use a key in the dictionary to access the value. In a Python dictionary, you can have multiple keys. These keys must be: Think of Python dictionaries as, well, dictionaries.

   Python Dictionaries: A Complete Overview • datagy

   datagy.io/python-dictionary/

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   What is a physical dictionary in Python?

   • For example, in a physical dictionary, the definition science that searches for patterns in complex data using computer methods is mapped to the key Data Science. In this Python tutorial, you'll learn how to create a Python dictionary, how to use its methods, and dictionary comprehension, as well as which is better: a dictionary or a list.

   Python Dictionaries: A Comprehensive Tutorial (with 52 Code ... - Dataq…

   www.dataquest.io/blog/python-dictionaries/

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3. realpython.com › python-dictsDictionaries in Python – Real Python

   realpython.com › python-dicts

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   Here’s what you’ll learn in this tutorial: You’ll cover the basic characteristics of Python dictionaries and learn how to access and manage dictionary data. Once you have finished this tutorial, you should have a good sense of when a dictionary is the appropriate data type to use, and how to do so.

   • Dictionaries in Python

     Python provides a composite data type called a dictionary,...

   • Take The Quiz

     Test your understanding of Python dictionaries. Python...

4. python.land › python-data-types › dictionariesPython Dictionary: How To Create And Use, With Examples

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   • Creating A Python Dictionary
   • Access and Delete A Key-Value Pair
   • Using Try… Except
   • Valid Dictionary Values
   • Valid Dictionary Keys
   • More Ways to Create A Python Dictionary
   • Dictionary View Objects
   • Merging Dictionaries
   • Comparing Python Dictionaries
   • Conclusion

   Let’s look at how we can create and use a Python dictionary in the Python REPL: A dictionary is created by using curly braces. Inside these braces, we can add one or more key-value pairs. The pairs are separated by commas when adding more than one key-value pair. The first dictionary in our example associates keys (names like Jack and Pete) with va...

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   Now that you’ve seen how to initialize a dictionary, let’s see how we can add and remove entries to an already existing one:

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   If a requested key does not exist, an exception of type KeyErroris thrown: If you know data can be missing, e.g., when parsing input from the outside world, make sure to surround your code with a try ... except KeyError. I’ve explained this in detail in the best practices section of my article on try… except. In that article, I also explain the con...

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   You can put anything in a dictionary. You’re not limited to numbers or strings. In fact, you can put dictionaries and Python listsinside your dictionary and access the nested values in a very natural way: Python’s JSON decoding and encoding libraryuses this feature of Python when parsing more complex JSON documents. It creates nested trees of lists...

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   You can go pretty wild on your dictionary keys, too. The only requirement is that the key is hashable. Mutable types like lists, dictionaries, and sets won’t work and result in an error like: TypeError: unhashable type: ‘dict’. Besides this limitation, you can use all data types as a dictionary key, including native types like a tuple, float and in...

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   Depending on your data source, there are more advanced ways to initialize a dictionary that might come in handy.

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   Some built-in dictionary methods return a view object, offering a window on your dictionary’s keys and values. Before we start using such view objects, there’s an important concept you need to understand: values in a view object change as the content of the dictionary changes.

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   If you’re running Python 3.9 or later, you can use the newly introduced merging operator for dictionaries: If you’re still on a Python version between 3.5 and 3.9, you can merge two dictionaries using the following method:

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   If you need to compare two dictionaries, you can use a comparison operator like this: This looks and sounds trivial, but it’s not! A dictionary can contain objects of any type, after all! Consequently, Python has to walk through all the keys and values and individually compare them. You might wonder if a dictionary with the same keys and values ins...

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   You’ve learned what a Python dictionary is, how to create dictionaries, and how to use them. We’ve examined many practical use cases involving Python dictionaries with example code. If there’s still something missing, or you simply want to learn even more about dictionaries, you can head over to the official manual page at Python.org.

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5. www.geeksforgeeks.org › python-dictionaryDictionaries in Python - GeeksforGeeks

   www.geeksforgeeks.org › python-dictionary

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   Apr 9, 2024 · Dictionaries in Python is a data structure, used to store values in key:value format. This makes it different from lists, tuples, and arrays as in a dictionary each key has an associated value. Note: As of Python version 3.7, dictionaries are ordered and can not contain duplicate keys. How to Create a Dictionary.

   • Video Duration: 3 min

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     Python Tutorial for Beginners 5: Dictionaries - Working with Key-Value Pairs

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7. www.dataquest.io › blog › python-dictionariesPython Dictionaries: A Comprehensive Tutorial (with 52 Code ...

   www.dataquest.io › blog › python-dictionaries

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   Apr 1, 2022 · Dictionaries in Python ; How dictionaries allow us to quickly access a certain Python object; Creating a dictionary with the dict() method or curly braces; Python dictionary methods; Looping through a dictionary; Creating frequency tables; Nested dictionaries; Dictionary comprehension; When to use a list or a dictionary; Using defaultdict() to ...

8. www.freecodecamp.org › news › python-dictionariesPython Dictionaries 101: A Detailed Visual Introduction

   www.freecodecamp.org › news › python-dictionaries

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   Dec 30, 2019 · Welcome. In this article, you will learn how to work with Python dictionaries, an incredibly helpful built-in data type that you will definitely use in your projects. In particular, you will learn: What dictionaries are used for and their main characteristics. Why they are important for your programming projects.

9. stackabuse.com › python-dictionary-tutorialGuide to Dictionaries in Python - Stack Abuse

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   Aug 31, 2023 · A Python dictionary is one such data structure that can store data in the form of key-value pairs - conceptually similar to a map. The values in a Python dictionary can be accessed using the keys. In this guide, we will be discussing Python dictionaries in detail.

10. datagy.io › python-dictionaryPython Dictionaries: A Complete Overview • datagy

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    Dec 10, 2021 · We have two main ways of accomplishing this: # Creating a Python Dictionary dictionary1 = {} dictionary2 = dict() We can check the type of these dictionaries by using the built-in type() function: # Checking Dictionary Types in Python print ( type (dictionary1)) print ( type (dictionary2))