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plotting streamplot is so slow in python3

I am using Anaconda, and I think this problem is even before I use Anaconda.
Everytime I want to plot streamline with basemap, it takes a very long time to plot one figure.
Here is an example:
import netCDF4 as nc
import matplotlib.pyplot as plt
import numpy as np
from mpl_toolkits.basemap import Basemap
fuv = nc.Dataset('~/era5_uv850_20200601_00_01.nc')
uwnd = fuv.variables['u']
vwnd = fuv.variables['v']
uwnd = uwnd[0,:,:]
vwnd = vwnd[0,:,:]
lon= fuv.variables['longitude']
lat= fuv.variables['latitude']
map = Basemap(projection='cyl',llcrnrlat= 0.,urcrnrlat=20.,llcrnrlon=90.5,urcrnrlon=120.5,resolution='i')
x,y=map(*np.meshgrid(lon,lat))
plt.clf()
map.streamplot(x,y,uwnd,vwnd,30)
map.drawcoastlines()
map.drawcountries()
plt.show()
The data from ERA5 webpage: Copernicus Data Storage
or you can download it here: WeTransfer Link
Is the slowness a common issue?

My plot bar graph isn't showing up. What's wrong with my code

import matplotlib as mpl
import matplotlib.pyplot as plt
%matplotlib inline
%matplotlib notebook
plt.figure(figsize=(12, 6))
CasData.pivot(index='year', columns='CasualtyNumber', values='People').plot(kind='bar')
plt.title('Casualties per year')
plt.xlabel('Year', fontsize=5)
plt.ylabel('Number of Casualties')
plt.show()
My plot bar graph using matplotlib.pyplot isn't showing.
I don't know why but my bar graph isn't showing. I've tried different ways.
If someone could help me out please. I'd appreciate it. Thank you.

Remove the line %matplotlib notebook.
It is overriding the previous line (these two lines are setting the backend). inline returns static plots, notebook is used for interactivity.
You also do not need the plt.show() line. This is taken care of by the inline backend.
This answer explains more about the backends: https://stackoverflow.com/a/43028034/6709902

I'm not really sure about your code as it seems incomplete but if you're using pivot I assumed you're pulling the data from a ".csv" file.
import matplotlib as mpl
import matplotlib.pyplot as plt
import pandas as pd
%matplotlib notebook
CasData = pd.read_csv('data.csv')
CasData.pivot_table(index='year', columns='CasualtyNumber', values='People').plot(kind='bar')
plt.title('Casualties per year')
plt.xlabel('Year',fontsize='5')
plt.ylabel('Number of Casualties')
plt.show()
You need to provide the data in order to plot something and I don't
see you providing any.

box plot not appearing in Google Colab

Trying to create a simple Box Plot using Google Colab for my Intro Python class. It is not appearing as I would like it. You can see my code and output below. I read in a file on NBA statistics, and my box plot would be based on a variable called "SHOT_CLOCK".
So far what I have:
import pandas as pd
from matplotlib import pyplot as plt
df = pd.read_csv('file path')
plt.boxplot(df['SHOT_CLOCK'], vert=False)
plt.title('Box Plot for SHOT_CLOCK')
plt.xlabel('Shot Clock')
plt.show()
Output:

Edit
In your example you are passing a Series object, try this way
plt.figure()
plt.title('Box Plot for SHOT_CLOCK')
plt.xlabel('Shot Clock')
df.boxplot(column='SHOT_CLOCK')

Once you add the following Import to your code it will work:
import matplotlib.pyplot as plt
plt.style.use('classic')
%matplotlib inline

How do you log stretch a FITS image and change its contrast?

I'm trying to use astropy 2.0.11 with python 2.7.15 to edit a fits image by applying a log stretch to it and change the contrast, and I have't been able to figure it out.
I've been trying to follow the tutorials on the astropy website for opening and manipulating fits files, but I'm wondering if the tutorials will only work for the latest version of astropy and on python 3?
Sorry about the organization of my code. This is prototype code and I'm just trying to test a few things and get this to work.
import time
import numpy as np
import matplotlib
import matplotlib.pyplot as plt
from matplotlib.colors import LogNorm
import astropy.visualization
from astropy.io import fits
from astropy.utils.data import download_file
from astropy.visualization import astropy_mpl_style
plt.style.use(astropy_mpl_style)
from astropy.utils.data import get_pkg_data_filename
def main():
#My own fits file
#fitsImage = get_pkg_data_filename("C:\\20180807T000456.fits")
fitsImage = download_file('http://data.astropy.org/tutorials/FITS-images/HorseHead.fits', cache=True )
hdu_list = fits.open(fitsImage)
hdu_list.info()
#norm = ImageNormalize(stretch=LogStretch())
image_data = fits.getdata(fitsImage)
print(type(image_data))
print(image_data.shape)
hdu_list.close()
plt.figure()
plt.imshow(image_data, cmap='gray', norm=LogNorm())
plt.colorbar()
# I chose the tick marks based on the histogram above
cbar = plt.colorbar(ticks=[5.e3,1.e4,2.e4])
cbar.ax.set_yticklabels(['5,000','10,000','20,000'])
time.sleep(10)
I am also unable to get the image to display with the plt.imshow()
Any insight would be helpful

You're so close! I ran your code in Python 2.7 and all you need to do is add
plt.show()
before time.sleep(10) (any reason you're including this?) and you get
Also, I don't think you need to include the colorbar and yticklabels, plt.imshow automatically adds the colorbar with the lognorm scale (I commented that section out when I got the image).

Making a chart bigger in size

I'm trying to get a bigger chart. However, the figure method from matplotlib does not seem to be working properly.
I get a message, which is not an error:
import pandas.io.data as web
import pandas as pd
import matplotlib.pyplot as plt
%matplotlib inline
...
plt.figure(figsize=(20,10))
df2['media']= df2['SPY']*.6 + df2['TLT']*.4
df2.plot()
plt.show()
What's wrong with my code?

You can skip the first plt.figure() and just use the argument figsize:
df2.plot(figsize=(20,10))
See docs.