Python dictionary only stores last values in new dictionary entries

Question

I have a netcdf file (data1) that contains (latitude, longitude, time) and I want to pull out specific (latitude, longitude) points. To do this, I use a dictionary.
lats=[20,40]
lons=[-135,-75]
names=['jib', 'jibb']
d={}
for i in lats:
    for j in lons:
        for k in names:
            d[k]=data1.sel(latitude=i).sel(longitude=j)

This is just an example where the data is meaningless. However, when I print out jib and jibb they have the same exact latitude and longitude. Why is this? What I want is for jib to have lat=20 and lon=-135, while jibb has lat=40 and lon=-75.
d['jib']

time: 44160
Coordinates:
longitude
()
float32
-75.0
latitude
()
float32
40.0

d['jibb']

time: 44160
Coordinates:
longitude
()
float32
-75.0
latitude
()
float32
40.0

Michael Guidry · Answer

Using zip() you can create a generator that loops over all of your iterables simultaneously. When iterables are zipped a new iterable is returned containing tuples of same-index values from each iterable that was provided.
#Example Zip Return ~ based on your data

names = ['jib', 'jibb']
lats  = [20,40]
lons  = [-135,-75]

print(list(zip(names, lats lons)))  #[('jib', 20, -135), ('jibb', 40, -75)]

When you use zip() in a generator you are simply unpacking those tuples at each iteration.
#Solution:

d = {k:data1.sel(latitude=lt).sel(longitude=ln) for k, lt, ln in zip(names, lats, lons)}

notes:

If the iterables provided to zip() have different lengths, the length of the iterable returned from zip() will be the same as the shortest iterable provided.
a = [1, 2, 3]
b = ['a', 'b']

print(list(zip(a, b)))  #[(1, 'a'), (2, 'b')]

The provided iterables do not have to match in type, they just have to qualify as an iterable type.
a = (1, 2, 3)
b = ['a', 'b', 'c']
c = range(3)

print(list(zip(a, b, c)))  #[(1, 'a', 0), (2, 'b', 1), (3, 'c', 2)]

Python dictionary only stores last values in new dictionary entries

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