#!/usr/bin/env python

# Author: Nageswara Rao
# F-strings are introduced in python 3.6. To use f-strings your python version should be >=3.6


# Simple example using format()
>>> name = 'Nageswara Rao'
>>> language = 'Python'
>>> old_style = 'Hai, I am {} and I am working on {}'.format(name, language)
>>> print(old_style)
Hai, I am Nageswara Rao and I am working on Python


# Using f string - Simple example
>>> name = 'Nageswara Rao'
>>> language = 'Python'
>>> with_f_string = f'Hai, I am {name} and I am working on {language}'
>>> print(with_format)
Hai, I am Nageswara Rao and I am working on Python

# We can do calculations also
>>> text = f'3 times 9 is equals to {3 * 9}'
>>> print(text)
3 times 9 is equals to 27


# Padding made easy - With out padding
>>> for n in range(0, 4):
...   text = f'The value is {n}'
...   print(text)
...
The value is 0
The value is 1
The value is 2
The value is 3

#  With padding - Leading 0 for single digits
>>> for n in range(0, 12):
...   text = f'The value is {n:02}'
...   print(text)
...
The value is 00
The value is 01
The value is 02
The value is 03
The value is 04
The value is 05
The value is 06
The value is 07
The value is 08
The value is 09
The value is 10
The value is 11

# Format longer floating poing
>>> from math import pi
>>> formatted_pi = f'Pi equals to {pi:.4f}'
>>> print(formatted_pi)
Pi equals to 3.1416 # See value formatted and also rounded off
>>> formatted_pi = f'Pi equals to {pi:.5f}'
>>> print(formatted_pi)
Pi equals to 3.14159

# Formatting date - How simple it is
>>> from datetime import datetime
>>> birthday = datetime(1992, 3, 5)
>>> format_birthday = f'Narendra has a birthday on {birthday:%B %d, %Y}'
>>> print(format_birthday)
Narendra has a birthday on January 03, 1990

# f-strings parsing is smart enough to handle named unicode code points
>>> ordinal, unicode = "Hello", "I'm an software engineer"
>>> print(f'{ordinal}, {unicode}')
Hello, I'm an software engineer