code: def latex_to_png(
      s,
      encode=False,
      backend=None,
      wrap=False,
      color="Black",
      scale=1.0,
  ):
      """Render a LaTeX string to PNG.
  
      Parameters
      ----------
      s : str
          The raw string containing valid inline LaTeX.
      encode : bool, optional
          Should the PNG data base64 encoded to make it JSON'able.
      backend : {matplotlib, dvipng}
          Backend for producing PNG data.
      wrap : bool
          If true, Automatically wrap `s` as a LaTeX equation.
      color : string
          Foreground color name among dvipsnames, e.g. 'Maroon' or on hex RGB
          format, e.g. '#AA20FA'.
      scale : float
          Scale factor for the resulting PNG.
      None is returned when the backend cannot be used.
  
      """
      s = cast_unicode(s)
      allowed_backends = LaTeXTool.instance().backends
      if backend is None:
          backend = allowed_backends[0]
      if backend not in allowed_backends:
          return None
      if backend == "matplotlib":
          f = latex_to_png_mpl
      elif backend == "dvipng":
          f = latex_to_png_dvipng
          if color.startswith("#"):
              # Convert hex RGB color to LaTeX RGB color.
              if len(color) == 7:
                  try:
                      color = "RGB {}".format(
                          " ".join(
                              [
                                  str(int(x, 16))
                                  for x in textwrap.wrap(color[1:], 2)
                              ]
                          )
                      )
                  except ValueError as e:
                      raise ValueError(
                          "Invalid color specification {}.".format(
                              color
                          )
                      ) from e
              else:
                  raise ValueError(
                      "Invalid color specification {}.".format(color)
                  )
      else:
          raise ValueError("No such backend {0}".format(backend))
      bin_data = f(s, wrap, color, scale)
      if encode and bin_data:
          bin_data = encodebytes(bin_data)
      return bin_data
  
imports: from io import BytesIO, open
  import os
  import tempfile
  import shutil
  import subprocess
  from base64 import encodebytes
  import textwrap
  from pathlib import Path
  from IPython.utils.process import find_cmd, FindCmdError
  from traitlets.config import get_config
  from traitlets.config.configurable import SingletonConfigurable
  from traitlets import List, Bool, Unicode
  from IPython.utils.py3compat import cast_unicode
label_desc: Use image node_id 1 for calling a global function with example usage: latex_to_png(s, encode, backend, wrap, color, scale) and returns: bin_data, None