code: def symbol(name: str=None, symbol_type: Type[Symbol]=Symbol) -> 'SymbolWildcard':
          
          if isinstance(name, type) and issubclass(name, Symbol) and symbol_type is Symbol:
              return SymbolWildcard(name)
          return SymbolWildcard(symbol_type, variable_name=name)
docs: Create a `SymbolWildcard` that matches a single `Symbol` argument.
  
          Args:
              name:
                  Optional variable name for the wildcard.
              symbol_type:
                  An optional subclass of `Symbol` to further limit which kind of symbols are
                  matched by the wildcard.
  
          Returns:
              A `SymbolWildcard` that matches the *symbol_type*.