Explain the function of static keyword and final keyword in Java in detail>>>
Error msg:
Unhandled exception in thread started by <function check_errors.<locals>.wrapper at 0x0000013E139A1488>
Traceback (most recent call last):
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\db\backends\mysql\base.py", line 26, in <module>
import MySQLdb as Database
ModuleNotFoundError: No module named 'MySQLdb'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\utils\autoreload.py", line 228, in wrapper
fn(*args, **kwargs)
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\core\management\commands\runserver.py", line 116, in inner_run
autoreload.raise_last_exception()
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\utils\autoreload.py", line 251, in raise_last_exception
six.reraise(*_exception)
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\utils\six.py", line 685, in reraise
raise value.with_traceback(tb)
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\utils\autoreload.py", line 228, in wrapper
fn(*args, **kwargs)
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\__init__.py", line 27, in setup
apps.populate(settings.INSTALLED_APPS)
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\apps\registry.py", line 108, in populate
app_config.import_models()
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\apps\config.py", line 202, in import_models
self.models_module = import_module(models_module_name)
File "C:\Users\w5659\Envs\py3\lib\importlib\__init__.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 994, in _gcd_import
File "<frozen importlib._bootstrap>", line 971, in _find_and_load
File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 678, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\contrib\auth\models.py", line 4, in <module>
from django.contrib.auth.base_user import AbstractBaseUser, BaseUserManager
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\contrib\auth\base_user.py", line 52, in <module>
class AbstractBaseUser(models.Model):
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\db\models\base.py", line 124, in __new__
new_class.add_to_class('_meta', Options(meta, app_label))
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\db\models\base.py", line 325, in add_to_class
value.contribute_to_class(cls, name)
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\db\models\options.py", line 214, in contribute_to_class
self.db_table = truncate_name(self.db_table, connection.ops.max_name_length())
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\db\__init__.py", line 33, in __getattr__
return getattr(connections[DEFAULT_DB_ALIAS], item)
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\db\utils.py", line 211, in __getitem__
backend = load_backend(db['ENGINE'])
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\db\utils.py", line 115, in load_backend
return import_module('%s.base' % backend_name)
File "C:\Users\w5659\Envs\py3\lib\importlib\__init__.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "C:\Users\w5659\Envs\py3\lib\site-packages\django\db\backends\mysql\base.py", line 30, in <module>
'Did you install mysqlclient or MySQL-python?' % e
django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module: No module named 'MySQLdb'.
Did you install mysqlclient or MySQL-python?
Question:
Version compatibility issues
Solution:
Method 1: install pymysql in the same level directory of setting.py__ init__. Add to py:
import pymysql
pymsql.install_ as_ MySQLdb()
Method 2: install mysqlclient, but you can’t install it directly. You can only use:
pip ins tallhttps://download.lfd.uci.edu/pythonlibs/h2ufg7oq/mysqlclient-1.3.13-cp36-cp36m-win_ amd64.whl
If it is 32-bit system Python 2.7, please modify it to mysqlclient-1.3.13-cp27-cp27m-win_ Amd32. WHL, the same as others