Explore advanced Python concepts and tools used by experienced Python developers.

Python for Programmers

In this module, we’ll explore advanced Python concepts and tools used by experienced Python developers. We'll begin by exploring Python modules and then move on to topics such as unicode, generators, and iterators. Lastly, we'll go over web-related tasks with Python, methods of testing code, and other useful skills.

Advanced Concepts in Python

Let's take a moment to learn some pattern matching basics. When using Python to look for a pattern in a string, we can use the `search` function like we did in the previous lesson.
 



# Pattern matching with `search()`
Here's how:

import re

text = "The ants go marching one by one"

strings = ['the', 'one']

for string in strings:
    match = re.search(string, text)
    if match:
        print('Found "{}" in "{}"'.format(string, text))
        text_pos = match.span()
        print(text[match.start():match.end()])
    else:
        print('Did not find "{}"'.format(string))


For this example, we import the `re` module and create a simple string (lines 1-3).
. Then we create a list of two strings that we'll search for in
the main string (Line 5). Next we loop over the strings (Line 7). We plan to search for and actually run a search for them. If there's a match, we print it out.
Otherwise, we tell the user that the `string` was not found.

There are a couple of other functions worth explaining in this example.
We are calling `span` in the above code which gives us the beginning and ending positions of the string that matched. 
 If we print out the
`text_pos` that we assigned the `span` to, we'll get a tuple like
this: (`21, 24`). Alternatively, we can just call some `match` methods, which is what we do next.  We use `start` and `end` to grab the
starting and ending position of the `match`, which should also be the two
numbers that we get from `span`.

# How escape codes can be helpful


There are also some sequences that we can search for using special escape codes in Python. Here's a quick list with brief explanations of
each:




Let's dig into some pattern matching using regular expressions and how escape codes can be helpful.


Pattern Matching Using Search and Escape Codes

Let's dig into some pattern matching using regular expressions and how escape codes can be helpful.