What do you wish you'd known about when you started learning Python? [closed]

Answer 1

Don't have variable names that are types. For example, don't name a variable "file" or "dict"

Answer 2

Most helpful: Dive Into Python. As a commenter points out, if you're learning Python 3, Dive Into Python 3 is more applicable.

Known about sooner: virtualenv.

Answer 3

Closures. Clean and concise, without having to resort to using a Strategy Pattern unlike languages such as Java

Answer 4

Tab completion and general readline support, including histories, even in the regular python shell.

$ cat ~/.pythonrc.py 
#!/usr/bin/env python

try:
    import readline
except ImportError:
    print("Module readline not available.")
else:
    import rlcompleter
    readline.parse_and_bind("tab: complete")

    import os
    histfile = os.path.join(os.environ["HOME"], ".pyhist")
    try:
        readline.read_history_file(histfile)
    except IOError:
        pass
    import atexit
    atexit.register(readline.write_history_file, histfile)
    del os, histfile

and then add a line to your .bashrc

export PYTHONSTARTUP=~/.pythonrc.py

These two things lead to an exploratory programming style of "it looks like this library might do what I want", so then I fire up the python shell and then poke around using tab-completion and the help() command until I find what I need.

Generators and list comprehensions are more useful than you might think. Don't just ignore them.

Answer 5

Functional programming tools, like all and any

Answer 6

I implemented plenty of recursive directory walks by hand before I learned about os.walk()