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Python Set Operations Explained: From Theory to Real-Time Applications

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A  set  in Python is an unordered collection of unique elements. It is useful when storing distinct values and performing operations like union, intersection, or difference. Real-Time Example: Removing Duplicate Customer Emails in a Marketing Campaign Imagine you are working on an email marketing campaign for your company. You have a list of customer emails, but some are duplicated. Using a set , you can remove duplicates efficiently before sending emails. Code Example: # List of customer emails (some duplicates) customer_emails = [ "alice@example.com" , "bob@example.com" , "charlie@example.com" , "alice@example.com" , "david@example.com" , "bob@example.com" ] # Convert list to a set to remove duplicates unique_emails = set (customer_emails) # Convert back to a list (if needed) unique_email_list = list (unique_emails) # Print the unique emails print ( "Unique customer emails:" , unique_email_list) Ou...
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5 Python File Modes You Need

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Here're top five Python file modes explained. The purpose is to open, read, write the files. There are occasions you need to deal with data, which is present in the files. You need to give correct file-modes to handle the files in Python.


Python file modes crucial to handle the files. Here is the list of file modes to use correctly in your program.
Python file open modes

5 Python File Modes You Need


Here's an example code how to you can use file mode:

  
filename = input('Enter a filename : ')
f1 = open(filename, 'mode')


1- Python File mode w 


To open the file for writing, you need 'w' mode. The beauty of this is If the file does not exist, it creates one. This mode's purpose is to write the file. If you try to read, you will get an error.



2- Python File mode w+


To Open the file for Reading and Writing, you need 'w+' mode. For instance, you used w+, you have tried to read the file - after writing, it displays blank. The reason is after writing cursor position will point at the end of the file.


3- Python File mode a


It appends the records at the end of the existing file. The file must exist to use this mode.


4- Python File mode r


To open a file in read-only mode. If the file does not exist, it throws an error.


5- Python File mode r+


Both read and write. When you write the data to the file, it writes at the end. Now, the cursor is at the end of the file. When you perform read, it gives blank.


In the 'r+' mode, if the file does not exist, and if you try to read, which gives an error.


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