GetReleaseDefinitions.
        [Preview API] Get a list of release definitions.
        :param str project: Project ID or project name
        :param str search_text: Get release definitions with names containing searchText.
        :param str expand: The properties that should be expanded in the list of Release definitions.
        :param str artifact_type: Release definitions with given artifactType will be returned. Values can be Build, Jenkins, GitHub, Nuget, Team Build (external), ExternalTFSBuild, Git, TFVC, ExternalTfsXamlBuild.
        :param str artifact_source_id: Release definitions with given artifactSourceId will be returned. e.g. For build it would be {projectGuid}:{BuildDefinitionId}, for Jenkins it would be {JenkinsConnectionId}:{JenkinsDefinitionId}, for TfsOnPrem it would be {TfsOnPremConnectionId}:{ProjectName}:{TfsOnPremDefinitionId}. For third-party artifacts e.g. TeamCity, BitBucket you may refer 'uniqueSourceIdentifier' inside vss-extension.json at https://github.com/Microsoft/vsts-rm-extensions/blob/master/Extensions.
        :param int top: Number of release definitions to get.
        :param str continuation_token: Gets the release definitions after the continuation token provided.
        :param str query_order: Gets the results in the defined order. Default is 'IdAscending'.
        :param str path: Gets the release definitions under the specified path.
        :param bool is_exact_name_match: 'true'to gets the release definitions with exact match as specified in searchText. Default is 'false'.
        :param [str] tag_filter: A comma-delimited list of tags. Only release definitions with these tags will be returned.
        :param [str] property_filters: A comma-delimited list of extended properties to be retrieved. If set, the returned Release Definitions will contain values for the specified property Ids (if they exist). If not set, properties will not be included. Note that this will not filter out any Release Definition from results irrespective of whether it has property set or not.
        :param [str] definition_id_filter: A comma-delimited list of release definitions to retrieve.
        :param bool is_deleted: 'true' to get release definitions that has been deleted. Default is 'false'
        :param bool search_text_contains_folder_name: 'true' to get the release definitions under the folder with name as specified in searchText. Default is 'false'.
        :rtype: [ReleaseDefinition]

def get_release_definitions(self, project, search_text=None, expand=None, artifact_type=None, artifact_source_id=None, top=None, continuation_token=None, query_order=None, path=None, is_exact_name_match=None, tag_filter=None, property_filters=None, definition_id_filter=None, is_deleted=None, search_text_contains_folder_name=None):
        """GetReleaseDefinitions.
        [Preview API] Get a list of release definitions.
        :param str project: Project ID or project name
        :param str search_text: Get release definitions with names containing searchText.
        :param str expand: The properties that should be expanded in the list of Release definitions.
        :param str artifact_type: Release definitions with given artifactType will be returned. Values can be Build, Jenkins, GitHub, Nuget, Team Build (external), ExternalTFSBuild, Git, TFVC, ExternalTfsXamlBuild.
        :param str artifact_source_id: Release definitions with given artifactSourceId will be returned. e.g. For build it would be {projectGuid}:{BuildDefinitionId}, for Jenkins it would be {JenkinsConnectionId}:{JenkinsDefinitionId}, for TfsOnPrem it would be {TfsOnPremConnectionId}:{ProjectName}:{TfsOnPremDefinitionId}. For third-party artifacts e.g. TeamCity, BitBucket you may refer 'uniqueSourceIdentifier' inside vss-extension.json at https://github.com/Microsoft/vsts-rm-extensions/blob/master/Extensions.
        :param int top: Number of release definitions to get.
        :param str continuation_token: Gets the release definitions after the continuation token provided.
        :param str query_order: Gets the results in the defined order. Default is 'IdAscending'.
        :param str path: Gets the release definitions under the specified path.
        :param bool is_exact_name_match: 'true'to gets the release definitions with exact match as specified in searchText. Default is 'false'.
        :param [str] tag_filter: A comma-delimited list of tags. Only release definitions with these tags will be returned.
        :param [str] property_filters: A comma-delimited list of extended properties to be retrieved. If set, the returned Release Definitions will contain values for the specified property Ids (if they exist). If not set, properties will not be included. Note that this will not filter out any Release Definition from results irrespective of whether it has property set or not.
        :param [str] definition_id_filter: A comma-delimited list of release definitions to retrieve.
        :param bool is_deleted: 'true' to get release definitions that has been deleted. Default is 'false'
        :param bool search_text_contains_folder_name: 'true' to get the release definitions under the folder with name as specified in searchText. Default is 'false'.
        :rtype: [ReleaseDefinition]
        """
        route_values = {}
        if project is not None:
            route_values['project'] = self._serialize.url('project', project, 'str')
        query_parameters = {}
        if search_text is not None:
            query_parameters['searchText'] = self._serialize.query('search_text', search_text, 'str')
        if expand is not None:
            query_parameters['$expand'] = self._serialize.query('expand', expand, 'str')
        if artifact_type is not None:
            query_parameters['artifactType'] = self._serialize.query('artifact_type', artifact_type, 'str')
        if artifact_source_id is not None:
            query_parameters['artifactSourceId'] = self._serialize.query('artifact_source_id', artifact_source_id, 'str')
        if top is not None:
            query_parameters['$top'] = self._serialize.query('top', top, 'int')
        if continuation_token is not None:
            query_parameters['continuationToken'] = self._serialize.query('continuation_token', continuation_token, 'str')
        if query_order is not None:
            query_parameters['queryOrder'] = self._serialize.query('query_order', query_order, 'str')
        if path is not None:
            query_parameters['path'] = self._serialize.query('path', path, 'str')
        if is_exact_name_match is not None:
            query_parameters['isExactNameMatch'] = self._serialize.query('is_exact_name_match', is_exact_name_match, 'bool')
        if tag_filter is not None:
            tag_filter = ",".join(tag_filter)
            query_parameters['tagFilter'] = self._serialize.query('tag_filter', tag_filter, 'str')
        if property_filters is not None:
            property_filters = ",".join(property_filters)
            query_parameters['propertyFilters'] = self._serialize.query('property_filters', property_filters, 'str')
        if definition_id_filter is not None:
            definition_id_filter = ",".join(definition_id_filter)
            query_parameters['definitionIdFilter'] = self._serialize.query('definition_id_filter', definition_id_filter, 'str')
        if is_deleted is not None:
            query_parameters['isDeleted'] = self._serialize.query('is_deleted', is_deleted, 'bool')
        if search_text_contains_folder_name is not None:
            query_parameters['searchTextContainsFolderName'] = self._serialize.query('search_text_contains_folder_name', search_text_contains_folder_name, 'bool')
        response = self._send(http_method='GET',
                              location_id='d8f96f24-8ea7-4cb6-baab-2df8fc515665',
                              version='5.1-preview.3',
                              route_values=route_values,
                              query_parameters=query_parameters)
        return self._deserialize('[ReleaseDefinition]', self._unwrap_collection(response))