title: How to import python extension module that has the same name as a pure python package with subpackages and modules?
body: <p>I have a project with pybind11 extension modules, structured in a hierarchical way.</p>
  
  <p>While importing, I face the following problem:</p>
  
  <h2>1. Test 1</h2>
  
  <h3>1.1. Package structure</h3>
  
  <pre><code>org
  ├── __init__.py
  ├── sdk
  │   ├── core.cpython-37m-x86_64-linux-gnu.so
  │   └── __init__.py
  └── sdk.cpython-37m-x86_64-linux-gnu.so
  </code></pre>
  
  <h3>1.2. Import type from module org.sdk:</h3>
  
  <pre><code>python -c "from org.sdk import CommonType"
  </code></pre>
  
  1.2.1. Fails with the error:
  
  <pre><code>ImportError: cannot import name 'CommonType' from 'org.sdk' (python3.7/site-packages/org_sdk-0.0.0-py3.7-linux-x86_64.egg/org/sdk/__init__.py)
  
  </code></pre>
  
  <h3>1.3. Import type from module org.sdk.core:</h3>
  
  <pre><code>python -c "from org.sdk.core import A"
  </code></pre>
  
  1.3.1. Success
  
  <h2>2. Test 2</h2>
  
  <p>Removed <code>org/sdk/__init__.py</code></p>
  
  <h3>2.1. Package structure</h3>
  
  <pre><code>org
  ├── __init__.py
  ├── sdk
  │   └── core.cpython-37m-x86_64-linux-gnu.so
  └── sdk.cpython-37m-x86_64-linux-gnu.so
  </code></pre>
  
  <h3>2.2. Import type from module org.sdk:</h3>
  
  <pre><code>python -c "from org.sdk import CommonType"
  </code></pre>
  
  2.2.1. Success
  
  <h3>2.3. Import type from module org.sdk.core:</h3>
  
  <pre><code>python -c "from org.sdk.core import A"
  </code></pre>
  
  2.3.1. Fails with the error:
  
  <pre><code>ModuleNotFoundError: No module named 'org.sdk.core'; 'org.sdk' is not a package
  </code></pre>
  
  <p>I'd like to know how can I have a solution where both imports would work?</p>
  
  <p>It seems that the default python loader, prefers the <code>org/sdk/__init__.py</code> to load the <code>org.sdk</code> package, is it possible to add some code in the org/sdk/<strong>init</strong>.py that would also load the pybind11 extension module <code>org/sdk.cpython-37m-x86_64-linux-gnu.so</code> ?</p>