class_docstr: A callable for converting CSS declarations to ExcelWriter styles
  
  Supports parts of CSS 2.2, with minimal CSS 3.0 support (e.g. text-shadow),
  focusing on font styling, backgrounds, borders and alignment.
  
  Operates by first computing CSS styles in a fairly generic
  way (see :meth:`compute_css`) then determining Excel style
  properties from CSS properties (see :meth:`build_xlstyle`).
  
  Parameters
  ----------
  inherited : str, optional
      CSS declarations understood to be the containing scope for the
      CSS processed by :meth:`__call__`.
code: def build_border(self, props):
      return {
          side: {
              "style": self._border_style(
                  props.get("border-{side}-style".format(side=side)),
                  props.get("border-{side}-width".format(side=side)),
              ),
              "color": self.color_to_excel(
                  props.get("border-{side}-color".format(side=side))
              ),
          }
          for side in ["top", "right", "bottom", "left"]
      }
  
imports: import itertools
  import re
  import warnings
  import numpy
  from pandas.compat import reduce
  from pandas.core.dtypes import missing
  from pandas.core.dtypes.common import is_float, is_scalar
  from pandas.core.dtypes.generic import ABCMultiIndex, ABCPeriodIndex
  from pandas import Index
  import pandas.core.common
  from pandas.io.formats.css import CSSResolver, CSSWarning
  from pandas.io.formats.format import get_level_lengths
  from pandas.io.formats.printing import pprint_thing
label_desc: Use image node_id 5 for calling the CSSToExcelConverter obj's underlying member method code with example usage: obj.build_border(props) and returns: unknown