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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def documentation(self, base_url=None, api_version=None, prefix=""):
 """Generates and returns documentation for this API endpoint"""

        documentation = OrderedDict()
        base_url = self.base_url if base_url is None else base_url
        overview = self.api.doc
        if overview:
            documentation['overview'] = overview

        version_dict = OrderedDict()
        versions = self.versions
        versions_list = list(versions)
        if None in versions_list:
            versions_list.remove(None)
        if False in versions_list:
            versions_list.remove(False)
        if api_version is None and len(versions_list) > 0:
            api_version = max(versions_list)
            documentation['version'] = api_version
        elif api_version is not None:
            documentation['version'] = api_version
        if versions_list:
            documentation['versions'] = versions_list
        for router_base_url, routes in self.routes.items():
            for url, methods in routes.items():
                for method, method_versions in methods.items():
                    for version, handler in method_versions.items():
                        if getattr(handler, 'private', False):
                            continue
                        if version is None:
                            applies_to = versions
                        else:
                            applies_to = (version, )
                        for version in applies_to:
                            if api_version and version != api_version:
                                continue
                            if base_url and router_base_url != base_url:
                                continue
                            doc = version_dict.setdefault(url, OrderedDict())
                            doc[method] = handler.documentation(doc.get(method, None), version=version, prefix=prefix,
                                                                base_url=router_base_url, url=url)
        documentation['handlers'] = version_dict
        return documentation