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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 slice_by_coord( self, start, end ):
 """ Return the slice of the component corresponding to a coordinate interval. start and end are relative to the + strand, regardless of the component's strand. """

        start_col = self.coord_to_col( start )
        end_col = self.coord_to_col( end )
        if (self.strand == '-'):
            (start_col,end_col) = (end_col,start_col)
        return self.slice( start_col, end_col )