Working with Text

Names typed into forms, product codes on labels, prices in a supplier's list, lines in a server log, messages from a support inbox: most of the data a program meets arrives as text, and almost none of it arrives clean. This track turns strings from something you print into something you can process with confidence. You will look closely at how strings behave, then clean messy input with strip, case and replace methods, split delimited text into fields and join it back, search and count inside text, and write validators for PIN codes, product codes, email addresses and phone numbers. You will format aligned reports and wrapped paragraphs, parse settings files, log lines and simple comma-separated data, and learn regular expressions step by step: matching, character classes and quantifiers, then groups, findall and substitution. A lesson on Unicode explains code points, UTF-8 bytes, normalisation and case-folding, with Arabic and accented examples.

The track is written for learners who already know variables, conditions, loops, functions and the core data structures (lists, tuples, dictionaries and sets). Every lesson uses realistic situations, such as customer records, invoices, receipts and delivery notes, and every exercise is checked automatically, including the awkward cases real data contains: empty strings, stray spaces, mixed capitals and non-English text. It ends with a mini project in five milestones: a web-server log analyzer that parses each line with a regular expression, counts status codes, ranks pages, charts traffic by hour and prints a formatted daily report.