Python Notes: Difference between revisions

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== datetime ==
== datetime ==
stuff
== tuples ==
<pre>
>>> x = [(1,2), (3,4), (5,6)]
>>> for item in x:
...    print "A tuple", item
A tuple (1, 2)
A tuple (3, 4)
A tuple (5, 6)
>>> for a, b in x:
...    print "First", a, "then", b
First 1 then 2
First 3 then 4
First 5 then 6
</pre>


== Exception handling ==
== Exception handling ==

Revision as of 18:28, 25 October 2017

Docs:

ghetto command line argv

#!/usr/bin/python

import sys

print 'Number of arguments:', len(sys.argv), 'arguments.'
print 'Argument List:', str(sys.argv)

what's in that object?

https://download.tuxfamily.org/jeremyblog/diveintopython-5.4/py/apihelper.py

/apihelper.py

/apihelper.py - short

then use it like this:

#!/usr/bin/env python

from apihelper import info

mything

info(mything)


AutoVivification

import pprint

class Vividict(dict):
    def __missing__(self, key):
        value = self[key] = type(self)()
        return value

d = Vividict()

d['foo']['bar']
d['foo']['baz']
d['fizz']['buzz']
d['primary']['secondary']['tertiary']['quaternary']
pprint.pprint(d)

vim tabs

in file:

# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4

in ~/.vimrc:

tabstop=8
expandtab
shiftwidth=4
softtabstop=4

parse json

python -m json.tool my_json.json


parse yaml

python -c "from yaml import load, Loader; load(open('filename.yml'), Loader=Loader)"

urllib

https://stackoverflow.com/questions/3238925/python-urllib-urllib2-post

datetime

stuff

tuples

>>> x = [(1,2), (3,4), (5,6)]
>>> for item in x:
...     print "A tuple", item
A tuple (1, 2)
A tuple (3, 4)
A tuple (5, 6)
>>> for a, b in x:
...     print "First", a, "then", b
First 1 then 2
First 3 then 4
First 5 then 6

Exception handling

try:
  # rv, data = M.search(None, "ALL")
  # rv, data = M.search(None, 'SENTSINCE 1-Jan-2017 SENTBEFORE 31-Dec-2017')
  rv, data = M.search(None, 'SENTSINCE 1 Jan 2017')
except Exception, e:
  print "M.search failed"
  print "Error %s" % M.error.message
  print "Exception is %s" % str(e)

also:

try:
    pass
except Exception as e:
    # Just print(e) is cleaner and more likely what you want,
    # but if you insist on printing message specifically whenever possible...
    if hasattr(e, 'message'):
        print(e.message)
    else:
        print(e)