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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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2 Exclusive Ways to Start Kafka Services

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The Kafka services start or stop you can do in two ways. Those are Systemd and Systemctl (sudo user). Below, you will find the commands for these two methods.


2 Ways to start Kafka Services


How to start/stop Kafka service

Here are exclusive ways. With these, you can start or stop Kafka services.  

1. Systemd service

The concept of unit files people who worked on Linux servers have familiarity with it. Also, they know creating the unit file to use by systemd.

To summarize, it initializes and maintains components throughout the system. This means that you can define ZooKeeper and Kafka as unit files, which then will be used by systems.


Commands

The first command starts the service, and the second command stops the service.

... [Service] ...

ExecStart=/opt/kafkainaction/bin/zookeeper-server-start.sh
ExecStop= /opt/kafkainaction/bin/zookeeper-server-stop.sh


2. Systemctl by Sudo (root) user

The root user can start or stop the Kafka services. This is more like front-end processing. This way of executing is called systemctl.

Commands

The first command starts the Zookeeper and the second one starts Kafka.

$sudo systemctl start zookeeper
$sudo systemctl start kafka

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