On 11/6/20 3:05 PM, Steve wrote:
"Right, because the name "datetime" points to the class datetime in the
module datetime.
The class, unlike the module, has no "datetime" attribute."
Ok, how do I unpoint/repoint a "datetime" to let the two locations work?
"Apologies if you already knew this. I wasn't sure."
Absolutely did not know any of this.
Libraries are a slow learning process for me....
The Python import command does some stuff behind the scenes, but from
the programmer viewpoint, you're just manipulating names in namespaces -
making a mapping of a name to the relevant object.
import boo
gives you a name 'boo' in the relevant namespace, which refers to the
module object made for boo when it was imported (that's some of the
behind the scenes stuff).
A quick interactive sample showing this in action:
>>> globals()
{'__name__': '__main__', '__doc__': None, '__package__': None,
'__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__':
None, '__annotations__': {}, '__builtins__': <module 'builtins' (built-in)>}
>>> import sys
>>> globals()
{'__name__': '__main__', '__doc__': None, '__package__': None,
'__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__':
None, '__annotations__': {}, '__builtins__': <module 'builtins'
(built-in)>, 'sys': <module 'sys' (built-in)>}
here's the case you are running into:
>>> import datetime
>>> globals()
{'__name__': '__main__', '__doc__': None, '__package__': None,
'__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__':
None, '__annotations__': {}, '__builtins__': <module 'builtins'
(built-in)>, 'datetime': <module 'datetime' from
'/usr/lib64/python3.8/datetime.py'>}
>>> from datetime import datetime
>>> globals()
{'__name__': '__main__', '__doc__': None, '__package__': None,
'__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__':
None, '__annotations__': {}, '__builtins__': <module 'builtins'
(built-in)>, 'datetime': <class 'datetime.datetime'>}
If you want to import the datetime class and still have the full
datetime module available, you can for example import as a different
name - here's a sample of that:
>>> import datetime as dt
>>> from datetime import datetime
>>> globals()
{'__name__': '__main__', '__doc__': None, '__package__': None,
'__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__spec__':
None, '__annotations__': {}, '__builtins__': <module 'builtins'
(built-in)>, 'dt': <module 'datetime' from
'/usr/lib64/python3.8/datetime.py'>, 'datetime': <class
'datetime.datetime'>}
Does this make it clearer?
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