How to access the variable declared in package init file when we use 'from package.subpackage import module'?

Question

When we use from package.subpackage import module , how can we access the package and subpackage init file variables from the calling module?

Assuming varname is name of variable in the __init__ file from both the package and package.subpackage , how can we access them in the calling module? Example:

• package.varname
• package.subpackage.varname

I know that if we had used 'import package.subpackage.module' then the above is possible but I am getting name is not defined error when I try to do the same using the from pkg.subpkg import mod approach since the package is not in the local namespace (only module is).

Answer 1

If a variable named varname is defined in the __init__.py module of a package named package , then we can access varname like this:

from package import varname
print(varname)

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Similarly, if a variable named varname is defined in the __init__.py module of the subpackage named subpackage of a package named package , then we can access varname like this:

from package.subpackage import varname
print(varname)

---

To access both of them at the same time we should take care of the naming conflict like this:

from package import varname as package_varname
from package.subpackage import varname as package_subpackage_varname
print(package_varname)
print(package_subpackage_varname)

---

Also, __init__.py allows us to define any variable at the package level. Doing so is often convenient if a module defines something that will be imported frequently. This pattern promotes adherence to the Pythonic flat is better than nested philosophy.

An example:

Suppose our project structure looks like:

/project
  - __init__.py
  - file1.py

And our file1.py looks like:

message = 'hi there'

Then we can access it like:

from project.file1 import message
print(message)

Now to make it accessible like:

from project import message

In the __init__.py we can do:

from .file1 import message

__all__ = ['message']