René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[BUG]Python API SPARQL Query Doesn't Work for HumanProteinOccurrence","articleBody":"**Describe the bug**\r\nThis query doesn't work.\r\n\r\n**To Reproduce**\r\nSteps to reproduce the behavior:\r\n1. Go to Colab Notebook\r\n2. Run:\r\n```python\r\nimport datacommons as dc\r\nroot = 'https://api.datacommons.org'\r\nquery_str = '''\r\nSELECT ?name ?pes_score ?rel_level\r\nWHERE { \r\n    ?a typeOf HumanProteinOccurrence . \r\n    ?a humanProteinOccurrenceReliability ?humanProteinOccurrenceReliability .\r\n    ?a proteinExpressionScore ?proteinExpressionScore .\r\n    ?a name ?name .\r\n    ?humanProteinOccurrenceReliability name ?rel_level .\r\n    ?proteinExpressionScore name ?pes_score}LIMIT 5\r\n'''\r\nresult = dc.query(query_str)\r\n```\r\n3. See error in the screenshot\r\n\r\n**Expected behavior**\r\nIt should return the query result. \r\n\r\n**Screenshots**\r\nhttps://screenshot.googleplex.com/2dbc2641-fd70-40d2-8a9f-2ddb3059ce7c\r\n\r\n**Additional context**\r\nThe relevant node in browser: https://datacommons.org/browser/bio/3BHS2_HUMAN_OralMucosa_SquamousEpithelialCells\r\n","author":{"url":"https://github.com/mengzhensun","@type":"Person","name":"mengzhensun"},"datePublished":"2020-08-18T23:44:16.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":0},"url":"https://github.com/141/api-python/issues/141"}