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              "value": "Although FITS keywords must be exclusively upper case, retrieving an item in a "
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              "value": " object is case insensitive."
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              "value": "FITS header class.  This class exposes both a dict-like interface and a list-like interface to FITS headers."
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              "value": "The header may be indexed by keyword and, like a dict, the associated value will be returned.  When the header contains cards with duplicate keywords, only the value of the first card with the given keyword will be returned. It is also possible to use a 2-tuple as the index in the form (keyword, n)--this returns the n-th value with that keyword, in the case where there are duplicate keywords."
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              "value": "Commentary keywords such as HISTORY and COMMENT are special cases: When indexing the Header object with either 'HISTORY' or 'COMMENT' a list of all the HISTORY/COMMENT values is returned      "
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