python - 似乎尽管导入了正确的库和模块，但 pycharm 仍然无法识别该库

Question

class Item(db.Model):
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(length=30), nullable=False, unique=True,) # create a Column object. db,Column takes an argument which shows the type of the Column, here we used db.String() method
price = db.Column(db.Integer, nullable=False,)
barcode = db.Column(db.String(length=12), nullable=False,Unique=True)
desc = db.Column(db.String(length=5000), nullable=False)

def __init__(self, **kwargs):
    self.name = kwargs.get('name')
    self.price = kwargs.get('price')
    self.barcode= kwargs.get('barcode')
    self.desc = kwargs.get('desc')

所以我正在尝试使用 SQLAlchemy 模块创建一个数据库。由于某种原因，这不起作用。我是一名初学者，并试图尽我所能找到解决方案，但他们都没有真正解决我的问题。我在执行时收到以下错误：

  File "D:/program_files/PyCharm Community Edition 2020.3.3/WEB/market.py", line 33, in <module>
    class Item(db.Model):
  File "D:/program_files/PyCharm Community Edition 2020.3.3/WEB/market.py", line 37, in Item
    barcode = db.Column(db.String(length=12), nullable=False,Unique=True)
  File "D:\program_files\PyCharm Community Edition 2020.3.3\WEB\venv\lib\site-packages\sqlalchemy\sql\schema.py", line 1471, in __init__
    self._extra_kwargs(**kwargs)
  File "D:\program_files\PyCharm Community Edition 2020.3.3\WEB\venv\lib\site-packages\sqlalchemy\sql\schema.py", line 1474, in _extra_kwargs
    self._validate_dialect_kwargs(kwargs)
  File "D:\program_files\PyCharm Community Edition 2020.3.3\WEB\venv\lib\site-packages\sqlalchemy\sql\base.py", line 292, in _validate_dialect_kwargs
    "named <dialectname>_<argument>, got '%s'" % k
TypeError: Additional arguments should be named <dialectname>_<argument>, got 'Unique'

Process finished with exit code 1

任何想法？谢谢

标签： pythonflasksqlalchemypycharm