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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 get_channels_by_sln_year_quarter( self, channel_type, sln, year, quarter):
 """ Search for all channels by sln, year and quarter """

        return self.search_channels(
            type=channel_type, tag_sln=sln, tag_year=year, tag_quarter=quarter)