Why can't find function's documentation?

WYBupup: <p>I am following the pytorch tutorial of <a href="https://pytorch.org/tutorials/intermediate/torchvision_tutorial.html" rel="noopener nofollow ugc">TORCHVISION OBJECT DETECTION FINETUNING TUTORIAL</a><br>
In this tutorial’s " An Instance segmentation model for PennFudan Datase" part. I found one class called torchvision.models.detection.mask_rcnn.MaskRCNNPredictor.<br>
<div class="lightbox-wrapper"><a class="lightbox" href="https://discuss.pytorch.org/uploads/default/original/3X/9/c/9c7d597a3a321352631f8388a51837d67c1afdea.png" data-download-href="https://discuss.pytorch.org/uploads/default/9c7d597a3a321352631f8388a51837d67c1afdea" title="function"><img src="https://discuss.pytorch.org/uploads/default/optimized/3X/9/c/9c7d597a3a321352631f8388a51837d67c1afdea_2_690x461.png" alt="function" data-base62-sha1="mkn2OU7AjLSkpCjeknk7748y5DQ" width="690" height="461" srcset="https://discuss.pytorch.org/uploads/default/optimized/3X/9/c/9c7d597a3a321352631f8388a51837d67c1afdea_2_690x461.png, https://discuss.pytorch.org/uploads/default/optimized/3X/9/c/9c7d597a3a321352631f8388a51837d67c1afdea_2_1035x691.png 1.5x, https://discuss.pytorch.org/uploads/default/original/3X/9/c/9c7d597a3a321352631f8388a51837d67c1afdea.png 2x" data-dominant-color="EDEDF0"><div class="meta"><svg class="fa d-icon d-icon-far-image svg-icon" aria-hidden="true"><use href="#far-image"></use></svg><span class="filename">function</span><span class="informations">1100×735 57.7 KB</span><svg class="fa d-icon d-icon-discourse-expand svg-icon" aria-hidden="true"><use href="#discourse-expand"></use></svg></div></a></div><br>
And I want to read the corresponding documentation to figure out the meaning of the parameters. However, the documentation page showed that there is not such class.<br>
<div class="lightbox-wrapper"><a class="lightbox" href="https://discuss.pytorch.org/uploads/default/original/3X/4/5/4574157af7af6743f976dfb346c2ab306a991598.png" data-download-href="https://discuss.pytorch.org/uploads/default/4574157af7af6743f976dfb346c2ab306a991598" title="QQ截图20200312235511"><img src="https://discuss.pytorch.org/uploads/default/optimized/3X/4/5/4574157af7af6743f976dfb346c2ab306a991598_2_690x91.png" alt="QQ截图20200312235511" data-base62-sha1="9UpEyiZPY1RnobufnlH6AHCdrn2" width="690" height="91" srcset="https://discuss.pytorch.org/uploads/default/optimized/3X/4/5/4574157af7af6743f976dfb346c2ab306a991598_2_690x91.png, https://discuss.pytorch.org/uploads/default/optimized/3X/4/5/4574157af7af6743f976dfb346c2ab306a991598_2_1035x136.png 1.5x, https://discuss.pytorch.org/uploads/default/optimized/3X/4/5/4574157af7af6743f976dfb346c2ab306a991598_2_1380x182.png 2x" data-dominant-color="F8F9F9"><div class="meta"><svg class="fa d-icon d-icon-far-image svg-icon" aria-hidden="true"><use href="#far-image"></use></svg><span class="filename">QQ截图20200312235511</span><span class="informations">1568×209 15.6 KB</span><svg class="fa d-icon d-icon-discourse-expand svg-icon" aria-hidden="true"><use href="#discourse-expand"></use></svg></div></a></div><br>
So, how can I search this class’s documentations?And I also find that I can’t find the explanation for attribute of class, such as what does “model.roi_heads” in the prior image mean…<br>
I would appreciate if someone could tell me the way.</p>

albanD: <p>It is because this is not the official API to use there models. You can find the official API <a href="https://pytorch.org/docs/master/torchvision/models.html#mask-r-cnn">here</a>.</p>

WYBupup: <p>Thanks for your quick response!</p>

WYBupup: <p>Would you please to tell me how to find documentation or code of the class or function which is not the official API. Since I have to know how to use these functions. For example, what does the MaskRCNNPredictor’s parameter mean?<br>
Since I am new to Pytorch, I am eager to learn the way.</p>

WYBupup: <p>Sorry for asking that obvious question. <img src="https://discuss.pytorch.org/images/emoji/apple/joy.png?v=9" title=":joy:" class="emoji" alt=":joy:"><br>
I am able to find the code of corresponding function or class by coping the code to Pycharm, push “ctrl” and clik the function to go to the code of the function.</p>