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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 is_compatible(self, obj):
 """Check if characters can be combined into a textline We consider characters compatible if: - the Unicode mapping is known, and both have the same render mode - the Unicode mapping is unknown but both are part of the same font """

        both_unicode_mapped = isinstance(self._text, str) and isinstance(obj._text, str)
        try:
            if both_unicode_mapped:
                return self.rendermode == obj.rendermode
            font0, _ = self._text
            font1, _ = obj._text
            return font0 == font1 and self.rendermode == obj.rendermode
        except (ValueError, AttributeError):
            return False