feat: getattr and iter dunders

[BobTheBuidler]

What I did

added getattr and iter dundermethods to the token manager

fixes: #

How I did it

n/a

How to verify it

try to iter and getattr

Checklist

• Passes all linting checks (pre-commit and CI jobs)
• New test cases have been added and are passing
• Documentation has been updated
• PR title follows Conventional Commit standard (will be automatically included in the changelog)

[antazoey]

I tried running:

[x for x in tokens]

but got this:

KeyError: "Symbol 'AZRX' is not a known token symbol"

In [2]: [x for x in tokens]

kinda weird. I do have multiple token lists installed though.

[antazoey]

I wonder if something like:

 def __iter__(self) -> Iterator[ContractInstance]:
        yielded = set()
        for token in self._manager.get_tokens(chain_id=self.provider.chain_id):
            if token.symbol in yielded:
                # Handle multiple lists.
                continue

            try:
                yield self[token.symbol]
            except KeyError:
                # Perhaps in another list?
                continue

            yielded.add(token.symbol)

would work for this situation.
I tried it again, except changed it to:

for x in tokens:
   ...:     print(x)

I see the first like hundred get printed out super fast, and then it suddenly is very slow at outputting them.
hmmmmm

[BobTheBuidler]

is it possible the slowness is from downloading the last of the tokenlists? Looking at this code again I'm not sure where else a slowdown might come from.

[BobTheBuidler]

I think this should be fixed now with my latest commit.

[antazoey]

I am getting the KeyError here when doing [x for x in token]

In [1]: [x for x in tokens]
---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
Cell In[1], line 1
----> 1 [x for x in tokens]

File ~/PycharmProjects/ape-tokens/ape_tokens/managers.py:124, in TokenManager.__iter__(self)
    122 def __iter__(self) -> Iterator[ContractInstance]:
    123     for token in self._manager.get_tokens(chain_id=self.provider.chain_id):
--> 124         yield self[token.symbol]

File ~/PycharmProjects/ape-tokens/ape_tokens/managers.py:137, in TokenManager.__getitem__(self, symbol)
    134         continue
    136 if token_info is None:
--> 137     raise KeyError(f"Symbol '{symbol}' is not a known token symbol")
    139 checksummed_address = to_checksum_address(token_info.address)
    140 try:

KeyError: "Symbol 'GETH' is not a known token symbol"