@property
    def _val_tmpl(self):
        return (
            '          <c:val{nsdecls}>\n'
            '            <c:numRef>\n'
            '              <c:f>{wksht_ref}</c:f>\n'
            '              <c:numCache>\n'
            '                <c:formatCode>General</c:formatCode>\n'
            '                <c:ptCount val="{val_count}"/>\n'
            '{val_pt_xml}'
            '              </c:numCache>\n'
            '            </c:numRef>\n'
            '          </c:val>\n'
        )
Return (a,b)-cosh/cosh pseudo-derivative of a periodic sequence.
dataset/ETHPy150Open scanny/python-pptx/pptx/chart/data.py/_SeriesData._val_tmpl--crossover with--dataset/ETHPy150Open scipy/scipy/scipy/fftpack/pseudo_diffs.py/cc_diff