code: def write_system_config(base_url, datadir, tooldir):
      
      out_file = os.path.join(datadir, "galaxy", os.path.basename(base_url))
      if not os.path.exists(os.path.dirname(out_file)):
          os.makedirs(os.path.dirname(out_file))
      if os.path.exists(out_file):
          # if no tool directory and exists, do not overwrite
          if tooldir is None:
              return out_file
          else:
              bak_file = out_file + ".bak%s" % (datetime.datetime.now().strftime("%Y%M%d_%H%M"))
              shutil.copy(out_file, bak_file)
      if tooldir:
          java_basedir = os.path.join(tooldir, "share", "java")
      rewrite_ignore = ("log",)
      with contextlib.closing(urllib_request.urlopen(base_url)) as in_handle:
          with open(out_file, "w") as out_handle:
              in_resources = False
              in_prog = None
              for line in (l.decode("utf-8") for l in in_handle):
                  if line[0] != " ":
                      in_resources = line.startswith("resources")
                      in_prog = None
                  elif (in_resources and line[:2] == "  " and line[2] != " "
                        and not line.strip().startswith(rewrite_ignore)):
                      in_prog = line.split(":")[0].strip()
                  # Update java directories to point to install directory, avoid special cases
                  elif line.strip().startswith("dir:") and in_prog and in_prog not in ["log", "tmp"]:
                      final_dir = os.path.basename(line.split()[-1])
                      if tooldir:
                          line = "%s: %s\n" % (line.split(":")[0],
                                               os.path.join(java_basedir, final_dir))
                      in_prog = None
                  elif line.startswith("galaxy"):
                      line = "# %s" % line
                  out_handle.write(line)
      return out_file
docs: Write a bcbio_system.yaml configuration file with tool information.