remove useless variable (#37)

* Update wallet.py

* Update build.yml

Author: kigawas

.github/workflows/build.yml

@@ -13,7 +13,7 @@ jobs:
   build:
     strategy:
       matrix:
-        python_version: ["3.6", "3.7", "3.8", "3.9.0-rc.1"]
+        python_version: ["3.6", "3.7", "3.8", "3.9"]
 
     runs-on: ubuntu-latest
 

bip44/wallet.py

@@ -17,7 +17,6 @@ def __init__(self, mnemonic: str, language: str = "english", passphrase: str = "
         :param language (str, optional): The mnemonic's language, default: "english"
         :param passphrase (str, optional): The mnemonic's passphrase, default: ""
         """
-        self._mnemonic = mnemonic
         self._seed = Mnemonic(language).to_seed(mnemonic, passphrase)
         self._bip32 = BIP32.from_seed(self._seed)