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Mastering flat_map in Python with List Comprehension

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Introduction In Python, when working with nested lists or iterables, one common challenge is flattening them into a single list while applying transformations. Many programming languages provide a built-in flatMap function, but Python does not have an explicit flat_map method. However, Python’s powerful list comprehensions offer an elegant way to achieve the same functionality. This article examines implementation behavior using Python’s list comprehensions and other methods. What is flat_map ? Functional programming  flatMap is a combination of map and flatten . It transforms the collection's element and flattens the resulting nested structure into a single sequence. For example, given a list of lists, flat_map applies a function to each sublist and returns a single flattened list. Example in a Functional Programming Language: List(List(1, 2), List(3, 4)).flatMap(x => x.map(_ * 2)) // Output: List(2, 4, 6, 8) Implementing flat_map in Python Using List Comprehension Python’...
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How to Search for Single CHAR in Python Using Regular-expression

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Here is the logic for searching single CHAR using regular expression(Regex). For instance, we use wildcards to search for anything on our computers. The Regex in Python works similarly.

Regular Expression


Regular expression

People use asterisk * for searching any document. For instance, if you type *.pdf, it returns all the pdfs available in the location (where you are conducting your search). Similar way, in Python, you can search using regular expressions.

Import Regex 

The first thing you need to do is import 're' if you want to work with regular expressions.


Example program: search for single CHAR

To match any single character, you can use [….]. Below, you will find an example to search for: 'l' or 'a' or 'b'

import re
pattern = r'[lab]' sequence = 'we love python' obj = re.search(pattern,sequence) if obj: print("We found a match here @",obj.group()) else: print("Sorry no match found.")
The word 'love' has the letter 'l'. Hence, a match is found.

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