[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-06-16 UTC."],[[["This function, `google.appengine.api.mail.invalid_headers_reason`, analyzes mail header values to identify the reason for their invalidity."],["The function requires a `headers` argument, which represents the header value that needs to be checked for validity."],["It returns a string detailing the cause of header invalidity if determinable, or `None` if the reason cannot be found."],["The function can be found in `google.appengine.api.mail.py` within the `appengine-python-standard` repository on Github."]]],[]]