class_docstr: Mixin class allowing to generate a link to the API documentation.
  
  This mixin relies on three attributes:
  - `_doc_link_module`: it corresponds to the root module (e.g. `sklearn`). Using this
    mixin, the default value is `sklearn`.
  - `_doc_link_template`: it corresponds to the template used to generate the
    link to the API documentation. Using this mixin, the default value is
    `"https://scikit-learn.org/{version_url}/modules/generated/
    {estimator_module}.{estimator_name}.html"`.
  - `_doc_link_url_param_generator`: it corresponds to a function that generates the
    parameters to be used in the template when the estimator module and name are not
    sufficient.
  
  The method :meth:`_get_doc_link` generates the link to the API documentation for a
  given estimator.
  
  This useful provides all the necessary states for
  :func:`sklearn.utils.estimator_html_repr` to generate a link to the API
  documentation for the estimator HTML diagram.
  
  Examples
  --------
  If the default values for `_doc_link_module`, `_doc_link_template` are not suitable,
  then you can override them:
  >>> from sklearn.base import BaseEstimator
  >>> estimator = BaseEstimator()
  >>> estimator._doc_link_template = "https://website.com/{single_param}.html"
  >>> def url_param_generator(estimator):
  ...     return {"single_param": estimator.__class__.__name__}
  >>> estimator._doc_link_url_param_generator = url_param_generator
  >>> estimator._get_doc_link()
  'https://website.com/BaseEstimator.html'
code: def _doc_link_template(self):
      sklearn_version = parse_version(__version__)
      if sklearn_version.dev is None:
          version_url = (
              f"{sklearn_version.major}.{sklearn_version.minor}"
          )
      else:
          version_url = "dev"
      return getattr(
          self,
          "__doc_link_template",
          (
              f"https://scikit-learn.org/{version_url}/modules/generated/"
              "{estimator_module}.{estimator_name}.html"
          ),
      )
  
imports: import html
  import itertools
  from contextlib import closing
  from inspect import isclass
  from io import StringIO
  from pathlib import Path
  from string import Template
  from ..None import __version__, config_context
  from .fixes import parse_version
label_desc: Use image node_id 1 for calling the _HTMLDocumentationLinkMixin obj's underlying member method code with example usage: obj._doc_link_template() and returns: getattr