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How to Read a CSV File from Amazon S3 Using Python (With Headers and Rows Displayed)

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  Introduction If you’re working with cloud data, especially on AWS, chances are you’ll encounter data stored in CSV files inside an Amazon S3 bucket . Whether you're building a data pipeline or a quick analysis tool, reading data directly from S3 in Python is a fast, reliable, and scalable way to get started. In this blog post, we’ll walk through: Setting up access to S3 Reading a CSV file using Python and Boto3 Displaying headers and rows Tips to handle larger datasets Let’s jump in! What You’ll Need An AWS account An S3 bucket with a CSV file uploaded AWS credentials (access key and secret key) Python 3.x installed boto3 and pandas libraries installed (you can install them via pip) pip install boto3 pandas Step-by-Step: Read CSV from S3 Let’s say your S3 bucket is named my-data-bucket , and your CSV file is sample-data/employees.csv . ✅ Step 1: Import Required Libraries import boto3 import pandas as pd from io import StringIO boto3 is...
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How to Use Python Try and Except Logic Correctly

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In Python, you can avoid exceptions using Try and Except logic. The Error-free programs save a lot of time. Also, you can keep away defects in production.
 

Python tips
How to Use Python Try and Except Logic Correctly


In Python, you can handle un-known errors by using TRY and EXCEPT logic. If the programmer does not take care of this, the default is for Python to print an error message and stops execution. 



So the responsibility of a programmer is upfront he/she has to find errors and handle them correctly. It is possible if you use the TRY and EXCEPT.


Python Syntax for Try and Except.


try:
      c = a/b
except:
      c = 1000000

Try ends with ':' it says that Try block start here. In this block, you can write actual logic. The Except: is another block. That means in this block programmer can specify some value. And that value populates when any error happens.

Try and Except Examples.

Example: 1.

Below is the example to give the expected error in except.

try:
      c = a/b
except ZeroDivisionError:
      c = 1000000


The above example is you can give a name to an error in Except.  When this error happens, it assigns 1000000.


Example: 2.

Below is an example to give anticipated errors.

try:
      c = a/b
except (ValueError, ZeroDivisionError):
      c = 1000000


Also, there can be many except statements associated with a single Try.

Example: 3.

Below is an example to use multiple excepts.

try:
      c = a/b
except ValueError:
    c = 0
except ZeroDivisionError:
      c = 1000000

And, as was mentioned, a variable can hold the value of the error to be caught:

Example: 4.

The below example is to assign a value to the variable when an error happens. 

k = ZeroDivisionError
try:
      c = a/b
except k:
      c = 1000000


If we left out the exception name, it assigns value C for other errors.

try:
      c = a/b
except:
      c = 0


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