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Using d3.select on a python-generated object

I'm using mpld3 to create a graph in a web app. I want to allow the user to drag the orange line.
I explicitly want to code this drag-and-drop behavior directly in d3.js, because d3.js allows me to set restrictions on the drag behavior (specifically I want to allow only horizontal drag, as shows in this JSFiddle.)
I am having trouble selecting the orange line element. I am getting its ID with mpld3.utils.get_id(), but passing this id on the JS side to either d3.select() or to mpld3.get_element() does not work.
import mpld3
import matplotlib.pyplot as plt
import numpy as np
x = np.linspace(-1,1,20)
fig, ax = plt.subplots()
ax.plot(x,x**3)
line = ax.plot([0,0],[-1,0])
js = '''
<script src="https://d3js.org/d3.v4.min.js"></script>
'''
html = mpld3.fig_to_html(fig)
print(mpld3.utils.get_id(line)) # gives something like 'el68722312816129664'
with open('pured3_output.html', 'w') as f:
f.write(html+js)
After opening pured3_output.html in the browser, I type this in the browser console:
>>> mpld3.get_element('el68722312816129664')
null
>>> d3.select('#el68722312816129664')
Selection {_groups: Array(1), _parents: Array(1)}
I don't know what it's returning but it's clearly not the right thing, because, d3.select('#el68722312816129664').remove() doesn't do anything.
I'm not particularly attached to using mpld3, compared to other packages built on top of d3.js, such as Plotly. I am using mpld3 so far because it seems simple and lightweight. (By the way, Plotly did not allow me to do what I wanted without touching the d3.js.). If this question is for some reason hard to solve in mpld3 (I don't see why it should be), please let me know how you would do it with a different package.

save instance of custom python class to file

I would like to save to a file multiple instances of a custom Python class.
The class is Loess, taken from https://github.com/joaofig/pyloess, which performs localised regression.
Below's a MWE of the saving process:
import pickle
import numpy as np
from Loess import Loess
xarr = np.linspace(0, 4, 100) * np.pi
yarr = 2*np.sin(xarr) + np.random.rand(len(xarr))
loess = Loess(xarr, yarr)
with open("localised_regression.pkl", "wb") as output:
pickle.dump(loess, output)
and now the retrieval process
import pickle
with open("localised_regression.pkl", 'rb') as input_:
localised_regression = pickle.load(input_)
When I do this on a jupyter notebook (run the first snippet on one notebook and the second on another) it works perfectly.
Dumping the instance of Loess from a notebook and retrieving it from terminal or another machine, it doesn't work.
I get ModuleNotFoundError: No module named 'Loess' error message
I even tried importing the module in python session where I attempt the retrieval, but nothing changes.
It seems that it only works from within the same location where the dumping was performed.
I'm using Python 3.7.7 and the same conda environment for both Python shell and jupyter notebook.
I examined other answers (like how to save/read class wholly in Python) but no luck.
I've tried saving to numpy file, but same story.
I've also tried dumping with marshal and json, but both complained.
Does anybody have a suggestion on how to solve this? Thank you

Is there a way to call and store data defined in a python script in to julia?

I have a python code which generates a weighted random graph. I want to use the weights generated in that code in a different Julia program. I am able to run the python code through Julia by using PyCall. But I am unable to get any of the data from the graph. Is there any way to do that?
The 'wt' stores the edge data in the python code.
When I am printing 'wt' in the python code it prints the nodes between which the edge is present and the weights.
This is giving me the required graph. I want to call 'wt' in Julia. How can I do that?
Python code
wt = G.edges.data('weight')
print(wt)
Julia code
using PyCall
y = py"exec(open('wtgraph.py').read())"

For your example it would be something like this (you didn't provide the complete code):
using PyCall
py"""
import something as G
def py_function(x):
return G.edges.data('weight')
"""
wt = py"py_function"('weight')

Python Spyder Display Symbolic Math

In Spyder 2 (Anaconda distribution) and in the IPython QT Console I'm able to print results of symbolic calculations (from an answer I got for a previous post) but I can't get equations in strings to print with the a IPython's Rich Display System:
from sympy import *
from IPython.display import display, Math
init_printing(use_unicode=False, wrap_line=False, no_global=True)
x, y, z = symbols('x y z')
#----- prints correctly
ii = integrate(x**2 + x + 1, x)
display(ii)
#----- does not print
Math(r'F(k) = \int_{-\infty}^{\infty} f(x) e^{2\pi i k} dx')
The above prints the results of the integrate correctly but the Math() does not print (no error -- just skips it). Note it all works in SciPy web notebook.
Thank you!

The Math class doesn't generate the rendered image from your Latex, that's why it doesn't work directly.
To get what you want you need to use this code
from IPython.display import Image, display
from IPython.lib.latextools import latex_to_png
eq = r'F(k) = \int_{-\infty}^{\infty} f(x) e^{2\pi i k} dx'
data = latex_to_png(eq, wrap=True)
display(Image(data=data))
Then you will see the right image

Hello guys im still having the problem, whe i use
from IPython.display import display, Math, Latex
display((Math(r'P(Purchase|Male)= \frac{Numero\ total\ de\ compras\ hechas\ por\ hombres\}{Total\ de\ hombres\ en\ el\ grupo\} = \frac{Purchase\cap Male}{Male}')))
on jupyter it works fine, but when i do the exact same code on spyder it doesnt work
im using python 3.6 , spyder 3.3.3
also i tried the marked asnwer but latex_to_png makes a NoneType Object on spyder

Use pylab to plot image returned from Scipy

I'm working to migrate from MatLab to python in Sage.
So I use these commands and I faced this error in Sage:
from scipy import misc
l = misc.lena();
import pylab as pl
pl.imshow(l)
The Error or message (i don't know) is:
matplotlib.image.AxesImage object at 0xb80198c
And it doesn't show any image

It's not an error, just print the object that method returned.
There are two ways to show the figure:
Add pl.show() after calling pl.imshow(l)
Use ipython --pylab to open your python shell,

That is an object being returned from pylab after using the "imshow" command. That is the location of the Axes image object.
documentation:
http://matplotlib.sourceforge.net/api/pyplot_api.html#matplotlib.pyplot.imshow
Looks like it says it displays the object to the current axes. If you havent already created a plot I imagine you wont see anything
Simple google search suggests this might be what you are looking for
http://docs.scipy.org/doc/scipy/reference/generated/scipy.misc.lena.html

from scipy import misc
l = misc.lena();
import pylab as pl
pl.imshow(l)
####use this
pl.show()