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How to get a complete list of object's methods and attributes?
does not return pattern as one of the lists's elements. Namely it returns:
5 Answers
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Difference between a theta join, equijoin and natural join
I'm having trouble understanding relational algebra when it comes to theta joins, equijoins and natural joins. Could someone please help me better understand it? If I use the = sign on a theta join is it exactly the same as just using a natural join?
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How to get instance variables in Python?
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Every object has a __dict__ variable containing all the variables and its values in it.
Try this
>>> hi_obj = hi()
>>> hi_obj.__dict__.keys()
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How can I dynamically create derived classes from a base class
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This bit of code allows you to create new classes with dynamic
names and parameter names.
The parameter verification in __init__ just does not allow
unknown parameters, if you need other verifications, like
type, or that they ar...
What is the difference between .*? and .* regular expressions?
I'm trying to split up a string into two parts using regex. The string is formatted as follows:
3 Answers
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Creating a dynamic choice field
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you can filter the waypoints by passing the user to the form init
class waypointForm(forms.Form):
def __init__(self, user, *args, **kwargs):
super(waypointForm, self).__init__(*args, **kwargs)
self.fields['waypoints'] = forms.ChoiceField(
choices=[(o.id, ...
Accessing dict keys like an attribute?
I find it more convenient to access dict keys as obj.foo instead of obj['foo'] , so I wrote this snippet:
27 Answers
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UML class diagram enum
...lared an attribute to be of type Integer. If your modeling tool has explicit support for enumerations, you should use that and only use the Class + <<enumeration>> stereotype notation as a fallback if necessary.
– Tom Morris
Feb 2 '12 at 17:11
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Can “using” with more than one resource cause a resource leak?
...lock for each variable.
The spec (§8.13) says:
When a resource-acquisition takes the form of a
local-variable-declaration, it is possible to acquire multiple
resources of a given type. A using statement of the form
using (ResourceType r1 = e1, r2 = e2, ..., rN = eN) statement
is pr...
Run function from the command line
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With the -c (command) argument (assuming your file is named foo.py):
$ python -c 'import foo; print foo.hello()'
Alternatively, if you don't care about namespace pollution:
$ python -c 'from foo import *; print hello()'
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