Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Peter Otten <__peter__@web.de>
Newsgroups: comp.lang.python
Subject: Re: A fun python CLI program for all to enjoy!
Date: Sat, 07 May 2016 15:59 +0200
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Xref: csiph.com comp.lang.python:108268

DFS wrote:

> getAddresses.py
> 
> Scrapes addresses from www.usdirectory.com and stores them in a SQLite
> database, or writes them to text files for mailing labels, etc
> 
> Now, just by typing 'fast food Taco Bell <city> 10 db all' you can find
> out how many Taco Bells are within 10 miles of you, and store all the
> addresses in your own address database.
> 
> No more convoluted Googling, or hitting the 'Next Page' button, or
> fumbling with the Yellow Pages...
> 
> Note: the db structure is flat on purpose, and the .csv files aren't
> quote delimited.
> 
> Put the program in its own directory.  It creates the SQLite database
> there, and writes files there, too.
> 
> Reviews of code, bug reports, criticisms, suggestions for improvement,
> etc are all welcome.

- Avoid module-level code and global variables
- Use functions that do one thing and operate on explicitly passed arguments
- You have 

if store == ...:
   ...

sprinkled across your module. You will have to change your code in many 
places if you want to add another output format. With a linear structure 
like

STORE_FUNCS = {
    "db": store_in_db,
    "txt": store_as_text,
    "csv": store_as_csv,
}

def main():
    args = read_arguments()
    records = read_records(args)
    records = unique(records)
    if args.limit:
        records = itertools.islice(records, args.limit)
    STORE_FUNCS[args.storage_format](args, records)

if __name__ == "__main__":
    main()

further enhancements will be a lot easier to implement.

The main() function avoids accidental uncontrolled globals. If you want one 
you have to declare it:

def main():
    global verbose
    args = read_arguments()
    verbose = args.verbose
    ...