Getting Started - Learn Python with BNHR

What is Python?¶

Python is a high-level general-purpose programming language. It is widely known because it is efficient and easy to learn. Contextualizing it, Python is a powerful tool for:

Data Cleaning: Automating the processing of thousands of survey records.
Analysis: Calculating crop yields, poverty incidence, and other statistics.
Geospatial Processing: Analyzing farm locations and land use.

You can read more about Python here: AWS: What is Python?

Kumusta mundo!¶

print("Kumusta mundo!")

Libraries and Modules¶

What are libraries?¶

A collection of pre-written code and functionalities that can be reused in other applications/scripts
Saves time and effort by providing ready-made solutions for common tasks
DRY principle - DON’T REPEAT YOURSELF

Python Standard Library

Comes bundled with Python and includes a wide range of modules for various tasks.
Examples include math for mathematical operations and os for interacting with the operating system.

Third-Party Libraries

Developed by the Python community or external developers.
Extend Python’s functionality beyond the standard library.
Examples include:
- numpy for numerical computing
- polars for lightning-fast dataframes
- duckdb for SQL queries directly embedded in Python code
Where to find? Try PyPI the Python Package Index.

How to Import a Library in Python?¶

We use the import keyword to bring a tool into our script.

Command	Explanation
`import math`	Imports the whole toolbox. You use it like `math.sqrt()`.
`import pandas as pd`	Imports it but gives it a nickname (`pd`) to save typing.
`from math import sqrt`	Imports only one specific tool.
`from math import *`	Imports everything blindly.

Source: Adapted from Python 3 Documentation: Modules

# Standard Library: Import math module
import math

num = 25
result = math.sqrt(num)
print(result)

# Import the srqt function from the math module
from math import sqrt

num = 25
result = sqrt(num)
print(result)

# Import everything from the math module
from math import *

num = 25
result = sqrt(num)
print(result)

Please avoid using the last method above. While this approach works, it is not recommended. Why do you think so?

# Rename while importing for easier typing later
import datetime as dt

print(dt.date.today())

# Will this work?
from datetime import date as d8

How will you get today’s date?

# Write your solution here