Analyse following RPM build log snippet. Describe contents accurately, without speculation or suggestions for resolution.            
Your analysis must be as concise as possible, while keeping relevant information intact.
Snippet: 
ValueError: invalid pyproject.toml config: `project.license`.
configuration error: `project.license` must be valid exactly by one definition (2 matches found):

    - keys:
        'file': {type: string}
      required: ['file']
    - keys:
        'text': {type: string}
      required: ['text']
The key "license" under section "project" in the file "pyproject.toml" contains string. But expected content is either "text" or "file" section.