class_docstr: Our base class for representing an html element along with a cascading style.
  The element is created along with a parent so that the StyleDict that we store
  can point to the parent's StyleDict.
code: def __init__(self, element, parent=None):
      self.element = element
      self.number_format = None
      parent_style = parent.style_dict if parent else None
      self.style_dict = StyleDict(
          style_string_to_dict(element.get("style", "")),
          parent=parent_style,
      )
      self._style_cache = None
  
imports: from openpyxl.cell import cell
  from openpyxl.styles import Font, Alignment, PatternFill, NamedStyle, Border, Side, Color
  from openpyxl.styles.fills import FILL_SOLID
  from openpyxl.styles.numbers import FORMAT_CURRENCY_USD_SIMPLE, FORMAT_PERCENTAGE
  from openpyxl.styles.colors import BLACK
label_desc: Use image node_id 1 to create a new Element object from inherited base classes: object with example: obj = Element(element, parent)