Import a list from a different file - python-2.7

Is there a way I can import a list from a different Python file? For example if I have a list:
list1 = ['horses', 'sheep', 'cows', 'chickens', 'dog']
Can I import this list into other files? I know to import other functions you do
from FileName import DefName
This is a user defined list and I don't want to have the user input the same list a million times.
Just a few maybes as to how this could be done:
from FileName import ListName or put all the lists into a function and then import the definition name
Thanks for the help

One option is to dump that list into a temp file, and read it from your other python script.
Another option (if one python script calls the other), is to pass the list as an argument (e.g. using sys.argv[1] and *args, etc).

I'll just export the lists in a file. Therefore every piece of code can read it.

Related

Python 'rawpy._rawpy.RawPy' object has no attribute 'imread' after second pass

I try to process a series of DNG raw picture files and it all works well for the first pass (first fils). When I try to read the second DNG file during the second pass through the for-next loop, I receive the error message 'rawpy._rawpy.RawPy' object has no attribute 'imread' when executing the line "with raw.imread(file) as raw:".
import numpy as np
import rawpy as raw
import pyexiv2
from scipy import stats
for file in list:
metadata = pyexiv2.ImageMetadata(file)
metadata.read()
with raw.imread(file) as raw:
rgb16 = raw.postprocess(gamma=(1,1), no_auto_bright=True, output_bps=16)
avgR=stats.describe(np.ravel(rgb16[:,:,0]))[2]
avgG=stats.describe(np.ravel(rgb16[:,:,1]))[2]
avgB=stats.describe(np.ravel(rgb16[:,:,2]))[2]
print i,file,'T=', metadata['Exif.PentaxDng.Temperature'].raw_value,'C',avgR,avgG,avgB
i+=1
I tried already to close the raw object but from googling I understand that is not necessary when a context manager is used.
Help or suggestions are very welcome.
Thanks in advance.
You're overwriting your alias of the rawpy module (raw) with the image you're reading. That means you'll get an error on the second pass through the loop.
import rawpy as raw # here's the first thing named "raw"
#...
for file in list:
#...
with raw.imread(file) as raw: # here's the second
#...
Pick a different name for one of the variables and your code should work.

how to Looping python scripts together

I have two files. An 'initialization' script aka file1.py and a 'main code' script aka 'main_code.py'. The main_code.py is really a several hundred line .ipynb that was converted to a .py file. I want to run the same skeleton of the code with the only adjustment being to pass in the different parameters found in the 'file1.py' script.
In reality, it is much more complex than what I have laid out below with more references to other locations / DBs and what not.
However, I receive errors such as 'each_item[0]' is not defined. I can't seem to be able to pass in the values/variables that come from my loop in file1.py to my script that is contained inside the loop.
Must be doing something very obviously wrong as I imagine this is a simple fix
file1.py:
import pandas as pd
import os
import bumpy as np
import jaydebeapi as jd
#etc...
cities = ['NYC','LA','DC','MIA'] # really comes from a query/column
value_list = [5,500,5000,300] # comes from a query/column
zipped = list(zip(cities,value_list)) # make tuples
for each_item in zipped:
os.system('python loop_file.py')
# where I'm getting errors.
main_code.py:
names = each_item[0]
value = each_item[1]
# lots of things going on here in real code but for simplicity...
print value = value * 4
print value

How to access a tempfile object across 2 separate requests (was:views) in Django

Can't find a direct, head on answer to this. Is there a way to access a tempfile in Django across 2 distinct views? Say I have the following code:
view#1(request):
temp = tempfile.NamedTemporaryFile()
write_book.save(temp_file)
temp_file_name = temp_file.name
print temp_file_name
request.session['output_file_name'] = temp_file_name
request.session.modified = True
return #something or other
view#2(request):
temp_file_name = request.session['output_file_name']
temp_file = open(str(temp_file_name))
#do something with 'temp_file' here
My problem comes in specifically on view#2, the 2nd line "open(temp_file_name)". Django complains this file/pathway doesn't exist, which is consistent of my understanding of the tempfile module (that the file is 'hidden' and only available to Django).
Is there a way for me to access this file? In case it matters, I ONLY need to read from it (technically serve it for download).
I'd think of this as how to access a NamedTemporaryFile across different requests, rather than different views. Looking at this documentation on NamedTemporaryFile, it says that the file can be opened across the same process, but not necessarily across multiple processes. Perhaps your other view is being called in a different Django process.
My suggestion would be to abandon the use of NamedTemporaryFile and instead just write it as a permanent file, then delete the file in the other view.
Thanks seddonym for attempting to answer. My partner clarified this for me...seddonym is correct for the Django version of NamedTemporaryFile. By calling the python version (sorry, don't have enough cred to post hyperlinks. Stupid rule) you CAN access across requests.
The trick is setting the delete=False parameter, and closing the file before 'returning' at the end of the request. Then, in the subsequent request, just open(file_name). Psuedo code below:
>>> import tempfile
>>> file = tempfile.NamedTemporaryFile(delete=False)
>>> file.name
'c:\\users\\(blah)\(blah)\(blah)\\temp\\tmp9drcz9'
>>> file.close()
>>> file
<closed file '<fdopen>', mode 'w+b' at 0x00EF5390>
>>> f = open(file.name)
>>> f
<open file 'c:\users\ymalik\appdata\local\temp\tmp9drcz9', mode 'r' at 0x0278C128>
This is, of course, done in the console, but it works in django as well.

How to save lists in python

I have a list including 4000 elements in python which each of its elements is an object of following class with several values.
class Point:
def __init__(self):
self.coords = []
self.IP=[]
self.BW=20
self.status='M'
def __repr__(self):
return str(self.coords)
I do not know how to save this list for future uses.
I have tried to save it by open a file and write() function, but this is not what I want.
I want to save it and import it in next program, like what we do in MATLAB that we can save a variable and import it in future
pickle is a good choice:
import pickle
with open("output.bin", "wb") as output:
pickle.dump(yourList, output)
and symmetric:
import pickle
with open("output.bin", "rb") as data:
yourList = pickle.load(data)
It is a good choice because it is included with the standard library, it can serialize almost any Python object without effort and has a good implementation, although the output is not human readable. Please note that you should use pickle only for your personal scripts, since it will happily load anything it receives, including malicious code: I would not recommend it for production or released projects.
This might be an option:
f = open('foo', 'wb')
np.save(f, my_list)
for loading then use
data = np.load(open('foo'))
if 'b' is not present in 'wb' then the program gives an error:
TypeError: write() argument must be str, not bytes
"b" for binary makes the difference.
Since you say Matlab, numpy should be an option.
f = open('foo', 'w')
np.save(f, my_list)
# later
data = np.load(open('foo'))
Of course, it'll return an array, not a list, but you can coerce it if you really want an array...

How to dynamically import and reimport a file containing definition of a global variable which may change anytime

I need to have actual state of my List, which may change anytime.
mylist.py
list = {"key": "value"}
For first time import it's state is actual, but list in mylist.py may be changed. I need to reimport it each time function is called.
somecode.py
def someFunc():
from mylist import list
print list
There is a function called reload(module)
import mylist
def someFunc():
mylist = reload(mylist) # this may raise syntaxerrors in wrong moments
list = mylist.list
print list
Does it work for you?