How can I use Tally in my code?

Question

I a computing the eigenvalues and eigenfunctions of a Laplacian on a unit square. I have written it as follows:
{ℒ, ℬ} = {-Laplacian[u[x, y], {x, y}],DirichletCondition[u[x, y] == 0, True]};
{vals, funs} = DEigensystem[{ℒ, ℬ}, u[x, y], {x, 0, 1}, {y, 0, 1}, 8];
vals

Therefore, I have received the list of first $8$ eigenvalues, that is:
$qquad {2pi^2,, 5pi^2,, 5pi^2,, 8pi^2,, 10pi^2,, 10pi^2,, 10pi^2,, 10pi^2 }$.
Now I want to use Tally to find the multiplicity of a specific eigenvalue (for example, take the eigenvalue $5pi^2$). I have no idea how to use Tally within the code written above. Please help me. I have read the reference  here, but I have no idea how to use it in my case.
Please help me.

Conor Cosnett · Accepted Answer

Tally can certainly count the occurrances of eigenvalues in your list called vals. For instance Tally[vals] tells me that there are $2$ instances of $10 pi^{2}$ and $2$ instance of $5 pi^{2}$.

Looking at Tally in the documentation I see that the word "multiplicities" means the number of instances of each distinct element in a list.

I notice that your code is producing a different vals in my notebook! Please quit your kernel and re-evaluate!

Also Wolfram mentions this in his documentation.

How can I use Tally in my code?

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