a = [1]
b = [2]
c = [3]
a += b if False else c
print(a) -sharp [1,3]
a = a + b if False else c
print(a) -sharp [3] 
a = [1]
b = [2]
c = [3]
a += b if False else c
print(a) -sharp [1,3]
a = a + b if False else c
print(a) -sharp [3] priority, the branches of a + b if False else c are a + b and c , which is equivalent to (a + b) if False else c ). You should expect a + (b if False else c) .
a + = b if False else c is equivalent to
if False:
a = a + b
else:
a = cthe settings of the webmaster document are as follows from pytz import utc from apscheduler.schedulers.background import BackgroundScheduler from apscheduler.jobstores.mongodb import MongoDBJobStore from apscheduler.jobstores.sqlalchemy import SQLAlche...
python3.6 pip 9.0.3 install shapely 1.6.4 error as shown in figure ...
check to see that celery and airflow, do not support Windows in the actual experiment. is there another way to implement this? can only reinstall a linux. ...
the data obtained from the database is such a dictionary { q_1 : 9, q_2 : 12, q3 : 22, q4 : 2, q5 : 6, w_1 : 9, w_2 : 12, w_3 : 22, w_4 : 2, w_5 : 6, e_1 : 9, e_2 : 12, e_3 : 22, e_4 : 2, e_5 : 6...
def f1(a, b, c=0, *args, **kw): print( a = , a, b = , b, c = , c, args = , args, kw = , kw) args = (1, 2, 3, 4) kw = { d : 99, x : -sharp } f1(*args, **kw) the result is a = 1 b = 2 c = 3 args = (4,) kw = { dink: 99...
for example, how to view the source code of python built-in functions give an example: -sharp xrang for i in xrange(10): print i -sharp -sharp pass class xrange(object): """ xrange(stop) -> xrange object xrange(star...
this big list data adds 100w pieces of data, take 1000 pieces of data from this big list at a time, and delete it from the list at present, my solution is: a = range(1000000) b=[] for i in range(1000): b.append(a.pop()) feels that this method is ...
insert but the data is a number, which is stored in the database as a string, and the corresponding field in the database is also of string type The python statement goes like this: sql = insert into uhaoma343 (riqi,uhaoma) values({},{}) .format(r...
there seem to be only six data types in python3 (strings, numbers, lists, dictionaries, tuples, collections), but I recently learned about the chapter on classes. 1 is an "instance " generated by class instantiation a data type? 2 are binary arrays an...
there is a python3 by default on the machine, but when you install pip3, you install another python3, because you only write scripts in python, so you don t need extra python,. How can you avoid this problem again? ...
I want to overload the multiplication operator of a vector. At the same time, you can calculate the vector vector, and the vector float v is the vector . def __mul__(v1, v2): return vec3(v1.e[0]*v2.e[0],v1.e[1]*v2.e[1],v1.e[2]*v2.e[2]) ...
for example, when I use kafka or rabbitmq to get data from a message queue, the source has only one queue and cannot offload data from the data source. However, it is difficult to calculate, so it is necessary to divert it internally. For example, my me...
I want to click the mouse to specify the coordinate location and specify the number of times. is there any shortcut? def click (num): mouseclick(xxx,xxx) ...
the crawler encountered an unknown parameter , which is used to request a URL. How to break a URL like:.. talk ExamCaseReportGeneral.jspx?case_id=612e24bf-eae7-4d22-ba4d-9d0169a5a5e6 ...
since python2, is installed by default in mac, now I want to use python3, , so I installed a python3, prompt Installed kernelspec python3 in usr local share jupyter kernels python3 on the terminal, indicating that the core installation of python3 is...
as the title I use the mac operating system, and have just come into contact with python . I have installed 3.6.1 before, but now the latest version of 3.6.x is 3.6.6 . I want to upgrade 3.6.1 in the system to 3.6.6 . Can you download and i...
< H2 > purpose < H2 > can dynamically call different py files, pass in parameters and get return parameters. Here is the imaginary implementation. a.py: path_file = b.py -sharp py para_in = 123 para_out = xxx(path_file,para_in) -sharp pat...
RT. the demand scenario is like this: made an app, notification of information + e-commerce for free, but I don t know what to push every day, so I wondered if I could monitor the peer s app notification, and then I also push this. There s really ...
users = [] data = {} for r in results: user = {} -sharp user[ select_id ] = r[0] -sharp user[ media_id ] = r[1] -sharp user[ user_id ] = r[2] -sh...
I want to insert 10 pieces of data into the array users_values.append((i, 75, 1, x[j] + .mp4 , str(uuid.uuid1()) + ".mp4", abc , 2018-08-01 06:21:37 , 2018-08-01 06:21:37 , 0, 0)) 10 pieces of da...