对Python来说真的很新。我有一个抽象基类BankAccount，有两个未实现的方法：存入和取出。
我创建了两个子类SavingsAccount和CurrentAccount。这两个子类旨在为方法提供实现：从抽象类继承的存入和撤销。
它在我的机器上工作得很好，但我一直收到这个错误：
from abc import ABCMeta, abstractmethod
^
SyntaxError: invalid syntax
在线上平台上，意图呈现。
这是我的代码：
from abc import ABCMeta, abstractmethod
class BankAccount:
__metaclass__ = ABCMeta
def __init__(self):pass
@abstractmethod
def deposit(self, amount):pass
@abstractmethod
def withdraw(self, amount):pass
class SavingsAccount(BankAccount):
def __init__(self):
self.balance = 500
def deposit(self, amount):
if 0 > amount:
return "Invalid deposit amount"
self.balance += amount
return self.balance
def withdraw(self, amount):
if 0 > amount:
return "Invalid withdraw amount"
elif self.balance - amount self.balance:
return "Cannot withdraw beyond the current account balance"
self.balance -= amount
return self.balance
class CurrentAccount(BankAccount):
def __init__(self):
self.balance = 0
def deposit(self, amount):
if 0 > amount:
return "Invalid deposit amount"
self.balance += amount
return self.balance
def withdraw(self, amount):
if 0 > amount:
return "Invalid withdraw amount"
elif amount > self.balance:
return "Cannot withdraw beyond the current account balance"
self.balance -= amount
return self.balance
已更新：完整错误日志
Traceback (most recent call last):
File "python/nose2/bin/nose2", line 8, in
discover()
File "/usr/local/lib/python2.7/dist-packages/nose2-0.5.0-py2.7.egg/nose2/main.py", line 300, in discover
return main(*args, **kwargs)
File "/usr/local/lib/python2.7/dist-packages/nose2-0.5.0-py2.7.egg/nose2/main.py", line 100, in __init__
super(PluggableTestProgram, self).__init__(**kw)
File "/usr/lib/python2.7/unittest/main.py", line 94, in __init__
self.parseArgs(argv)
File "/usr/local/lib/python2.7/dist-packages/nose2-0.5.0-py2.7.egg/nose2/main.py", line 133, in parseArgs
self.createTests()
File "/usr/local/lib/python2.7/dist-packages/nose2-0.5.0-py2.7.egg/nose2/main.py", line 258, in createTests
self.testNames, self.module)
File "/usr/local/lib/python2.7/dist-packages/nose2-0.5.0-py2.7.egg/nose2/loader.py", line 67, in loadTestsFromNames
for name in event.names]
File "/usr/local/lib/python2.7/dist-packages/nose2-0.5.0-py2.7.egg/nose2/loader.py", line 82, in loadTestsFromName
result = self.session.hooks.loadTestsFromName(event)
File "/usr/local/lib/python2.7/dist-packages/nose2-0.5.0-py2.7.egg/nose2/events.py", line 224, in __call__
result = getattr(plugin, self.method)(event)
File "/usr/local/lib/python2.7/dist-packages/nose2-0.5.0-py2.7.egg/nose2/plugins/loader/testclasses.py", line 119, in loadTestsFromName
result = util.test_from_name(name, module)
File "/usr/local/lib/python2.7/dist-packages/nose2-0.5.0-py2.7.egg/nose2/util.py", line 106, in test_from_name
parent, obj = object_from_name(name, module)
File "/usr/local/lib/python2.7/dist-packages/nose2-0.5.0-py2.7.egg/nose2/util.py", line 117, in object_from_name
module = __import__('.'.join(parts_copy))
File "/home/ubuntu/Applications/andelabs-server/tmp/57d7029af597c64100ba88a5-57bc46aae713b01900df735e-test.py", line 4, in
from tmp.andelabs_57d7029af597c64100ba88a5_57bc46aae713b01900df735e import *
File "/home/ubuntu/Applications/andelabs-server/tmp/andelabs_57d7029af597c64100ba88a5_57bc46aae713b01900df735e.py", line 1
from abc _import_ ABCMeta, abstractmethod
^
SyntaxError: invalid syntax