code: def test_custom1():
      # Removes the parser's ability to understand \cdot and \div.
  
      parser = init_custom_parser(modification1)
  
      with raises(lark.exceptions.UnexpectedCharacters):
          parser.doparse(r"a \cdot b")
          parser.doparse(r"x \div y")
  
file_path: sympy/sympy/parsing/tests/test_custom_latex.py
imports: import os
  import tempfile
  import sympy
  from sympy.testing.pytest import raises
  from sympy.parsing.latex.lark import LarkLaTeXParser, TransformToSymPyExpr, parse_latex_lark
  from sympy.external import import_module
label_desc: Use image node_id 2 for calling a global function with example usage: test_custom1() without return types