Functions, namespace, memory management

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Next: Comprehension, generators, iteration

Required course material for the lesson

Powerpoint: Functions - this will be short as it is a reminder.
Powerpoint: Namespace.
Powerpoint: Memory management.
Video: Functions in Python
Video: Examples and identifying data types
Resource: Example code - Functions
Video: Live Coding

Subjects covered

• Short about functions
• Namespace in Python
• Memory management

Exercises to be handed in

The 2 first exercises are re-use from earlier. It is for a good purpose as will be seen later.
You go back to solo git use to maintain your git skills. Commit every exercise to your private exercise repository.

1. Make a function fastaread(filename) which takes a filename as a parameter and returns 2 lists, first list is the headers, second list is the sequences (as single strings without whitespace). Add appropriate error handling to the function. You can test your function on the file dna7.fsa. In order to test at use the function you must build a small program around it.
2. Make a function fastawrite(filename, headers, sequences) which takes a filename, a list of headers and a corresponding list of sequences as parameters and writes the fasta file. Add appropriate error handling to the function. You can test your function on the file dna7.fsa. Build a small program around your function. If you first read the file with fastaread and then write a new file with fastawrite, then if the files are identical, you know you have done right.