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tycho_client/tycho/models.py

@@ -5,7 +5,7 @@ from fractions import Fraction
 from logging import getLogger
 from typing import Union
 
-from pydantic import BaseModel, Field
+from pydantic import BaseModel, Field, PrivateAttr
 
 Address = str
 
@@ -30,6 +30,7 @@ class EthereumToken(BaseModel):
     address: str
     decimals: int
     gas: Union[int, list[int]] = 29000
+    _hash: int = PrivateAttr(default=None)
 
     def to_onchain_amount(self, amount: Union[float, Decimal, str]) -> int:
         """Converts floating-point numerals to an integer, by shifting right by the
@@ -62,7 +63,7 @@ class EthereumToken(BaseModel):
 
         Quantize is needed for UniswapV2.
         """
-        with localcontext(self._dec_context):
+        with localcontext(Context(rounding=ROUND_FLOOR, prec=256)):
             if isinstance(onchain_amount, Fraction):
                 return (
                     Decimal(onchain_amount.numerator)
@@ -80,6 +81,22 @@ class EthereumToken(BaseModel):
                 amount = Decimal(str(onchain_amount)) / Decimal(10 ** self.decimals)
             return amount
 
+    def __repr__(self):
+        return self.symbol
+
+    def __str__(self):
+        return self.symbol
+
+    def __eq__(self, other) -> bool:
+        # this is faster than calling custom __hash__, due to cache check
+        return other.address == self.address
+
+    def __hash__(self) -> int:
+        if self._hash is None:
+            # caching the hash saves time during graph search
+            self._hash = hash(self.address)
+        return self._hash
+
 
 class DatabaseType(Enum):
     # Make call to the node each time it needs a storage (unless cached from a previous call).