How to use items in python

To create a Python virtual environment, you can use the venv module. The steps are: 1. Enter the project directory to execute the python-mvenvenv environment to create the environment; 2. Use sourceenv/bin/activate to Mac/Linux and env\Scripts\activate to Windows; 3. Use the pipinstall installation package, pipfreeze>requirements.txt to export dependencies; 4. Be careful to avoid submitting the virtual environment to Git, and confirm that it is in the correct environment during installation. Virtual environments can isolate project dependencies to prevent conflicts, especially suitable for multi-project development, and editors such as PyCharm or VSCode are also

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UsezoneinfoforPython3.9 tocreatetimezone-awaredatetimesandconvertbetweentimezoneswithastimezone();2.ForPython3.6–3.8,usepytzwithlocalize()toavoidDSTerrors;3.AlwaysworkinUTCinternallyandconverttolocaltimeonlyfordisplay;4.Parsetimezone-awarestringsusin

The method of filling Excel data into web forms using Python is: first use pandas to read Excel data, and then use Selenium to control the browser to automatically fill and submit the form; the specific steps include installing pandas, openpyxl and Selenium libraries, downloading the corresponding browser driver, using pandas to read Name, Email, Phone and other fields in the data.xlsx file, launching the browser through Selenium to open the target web page, locate the form elements and fill in the data line by line, using WebDriverWait to process dynamic loading content, add exception processing and delay to ensure stability, and finally submit the form and process all data lines in a loop.

To sort the values of the dictionary, use the sorted() function to match the dict.items() and key parameters; 1. Use lambdaitem:item[1] to sort by ascending order; 2. Add reverse=True to implement descending order; 3. Use operator.itemgetter(1) to replace lambda to improve readability and performance; the dictionary maintains the insertion order in Python 3.7, the original dictionary remains unchanged, and returns a new dictionary. If the value types are mixed, additional processing is required, and the final pattern is dict(sorted(d.items(), key=lambdax:x[1])).

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To beautify and print JSON files, you need to use the indent parameters of the json module. The specific steps are: 1. Use json.load() to read the JSON file data; 2. Use json.dump() and set indent to 4 or 2 to write to a new file, and then the formatted JSON file can be generated and the beautified printing can be completed.

Create a virtual environment: Run python-mvenvvenv in the project folder. 2. Activate the virtual environment: Windows uses venv\Scripts\activate, macOS/Linux uses sourcevenv/bin/activate. 3. Open the project in VSCode and press Ctrl Shift P to select the Python interpreter, specify the interpreter in the virtual environment. 4. Verify whether it is effective: run importsys;print(sys.executable), and the output path should point to the venv folder. 5. Optional configuration: enable python.terminal.a in settings