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Reuse of primitive objects

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An interesting thing to note which may help optimize your applications is that primitives are actually also refcounted under the hood. Let’s take a look at numbers; for all integers between -5 and 256, Python always reuses the same object: 

>>> import sys
>>> sys.getrefcount(1)
797
>>> a = 1
>>> b = 1
>>> sys.getrefcount(1)
799

Note that the refcount increases, meaning that a and b reference the same underlying object when they refer to the 1 primitive. However, for larger numbers, Python actually doesn’t reuse the underlying object: 

>>> a = 999999999
>>> sys.getrefcount(999999999)
3
>>> b = 999999999
>>> sys.getrefcount(999999999)
3

Because the refcount for 999999999 does not change when assigning it to a and b we can infer that they refer to two different underlying objects, even though they both are assigned the same primitive.

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Garbage Collection:
* Garbage Collection
* Reuse of primitive objects
* Effects of the del command
* Reference Counting
* Garbage Collector for Reference Cycles
* Viewing the refcount of an object
* Forcefully deallocating objects
* Managing garbage collection
* Do not wait for the garbage collection to clean up
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0 Getting Started
1 List comprehension
2 Filter
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68 pip PyPI Package Manager
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79 PyInstaller - Distributing Python Code
80 Iterables and Iterators
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98 PostgreSQL
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116 List destructuring
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120 ArcPy
121 Python Anti-Patterns
122 Plugin and Extension Classes
123 Websockets
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135 Unicode
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154 Audio
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156 queue module
157 ijson
158 webbrowser module
159 base64 module
160 Flask
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162 Sockets and Message Encryption / Decryption
163 pygame
164 Input Subset and Output External Data Files using Pandas
165 hashlib
166 Gzip
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168 Creating a Windows Service
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170 configparser
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172 Optical Character Recognition OCR
173 Python Data Types
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176 Unzipping Files
177 Functional Programming
178 Python Virtual Environment - virtualenv
179 sys module
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181 virtualenvwrapper on Windows
182 Python Requests Post
183 Plotting with Matplotlib
184 Python Lex-Yacc
185 pyaudio
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187 pip and PyPI Package Manager
188 Writing to CSV from String or List
189 Raise Custom Errors Exceptions
190 Using loops within functions
191 Contributors