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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 html_entity_decode_char(self, m, defs=htmlentities.entitydefs):
 """ decode html entity into one of the html char """

        try:
            char = defs[m.group(1)]
            return "&{char};".format(char=char)
        except ValueError:
            return m.group(0)
        except KeyError:
            return m.group(0)