Python __dict__ conversion to kwargs [duplicate] - python

This question already has answers here:
Converting Python dict to kwargs?
(3 answers)
Closed 5 years ago.
I want to build a query for sunburnt(solr interface) using class inheritance and therefore adding key - value pairs together. The sunburnt interface takes keyword arguments. How can I transform a dict ({'type':'Event'}) into keyword arguments (type='Event')?

You can do this using dictionary unpacking:
dct = dict({'type':'Event'})
# equivalent to func(type='Event')
func(**dct)

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I am trying to initialize a list object in python that accepts only one data type, let's say that I want to make a list of integers in c++, I would write int list[] = {1,2,3};, what is the python equivalent of this?

Pass list items as arguments to method [duplicate]

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How to extract parameters from a list and pass them to a function call [duplicate]
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How to split list and pass them as separate parameter?
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Assuming i have a method definition like this do_stuff(*arg).
I have a list of values, ['a','b',...]. How best can i pass the values of this list as individual arguments to the do_stuff method as do_stuff('a','b',...) ?
I've unsuccessfully tried using list comprehension - do_stuff([str(value) for value in some_list])
I am hoping i don't have to change do_stuff() to accept a list
Any pointers would be appreciated.
You can pass them using the "*" operator. So an example would be like this:
def multiplyfouritems(a,b,c,d):
return a*b*c*d
multiplyfouritems(*[1,2,3,4])
It's the same syntax, with the *:
do_stuff(*['a','b','c'])

Python sort function explanation [duplicate]

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What algorithm does Python's built-in sort() method use?
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What is `lambda` in Python code? How does it work with `key` arguments to `sorted`, `sum` etc.?
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I found the following line of code which I'm unable to google as it has a custom function. Can someone please explain this?
list.sort(key=lambda v: map(int, v.split('.')))
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How to pass a list as a function's arguments [duplicate]

This question already has answers here:
Expanding tuples into arguments
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Closed 8 months ago.
If I have a function:
def run(time, message, time_span_pattern):
...
And a list like:
run_args = ['1s', '1 second alarm', <_sre.SRE_Pattern object at 0x100435680>]
How can I pass the list, as separate arguments, to run? Is there a builtin way to do this, or am I forced to reference each element individually and by index?
You're looking for:
run(*run_args)
This is explained in more detail in this StackOverflow answer about the star and double star operator
It's also covered in the python docs

List of strings. New variables with those name (without classes). Python [duplicate]

This question already has answers here:
How can you dynamically create variables? [duplicate]
(8 answers)
Closed 8 years ago.
if one had a list of strings, how could they create variables (empty list objects) with those names?
pre_vars= ['list_1','list_2','list_3']
print list_1,list_2,list_3
>>> [],[],[]
I saw some examples that were similar but they were using classes. Can this be done without using classes?
Use globals():
for name in pre_vars:
globals()[name]= []

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