The difference between "import package.module" and "from packageimport module"(about pymol)

[Xiao Jianfeng]

Hello,

In pymol I can use "from chempy import Atom" but "import chempy.Atom"
doesn't work.
It says,"ImportError: No module named Atom". What is going wrong ?

Thanks

 

[Dennis Lee Bieber]

Hello,

In pymol I can use "from chempy import Atom" but "import chempy.Atom"
doesn't work.
It says,"ImportError: No module named Atom". What is going wrong ?

"from X import Y" says: read module (file) X, make a LOCAL binding
named Y to the Y object found inside module X.

"import X.Y" says: find the MODULE (file) Y located in the PACKAGE
(directory) X
--

 

[Ben Finney]

In pymol I can use "from chempy import Atom" but "import chempy.Atom"
doesn't work.
It says,"ImportError: No module named Atom". What is going wrong ?

I would trust the error message first, and check your assumption.

Is 'chempy' actually a package, containing an 'Atom' module? Or is
'chempy' actually a module, containing an 'Atom' attribute?