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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def getAvailableGlyphnames(self):
 """ Return a list of all glyphnames we have masters for."""

        glyphNames = {}
        for locationName, (source, loc) in self.sources.items():
            for glyph in source:
                glyphNames[glyph.name] = 1
        names = sorted(glyphNames.keys())
        return names