docs: def general_settings():
      """general settings
      """
      import matplotlib as mpl
      import matplotlib.pyplot as plt
      mpl.rcParams['font.size'] = 7.0
      mpl.rcParams['axes.labelsize'] = 7.0
      mpl.rcParams['xtick.labelsize'] = 7.0
      mpl.rcParams['ytick.labelsize'] = 7.0
      mpl.rcParams["lines.linewidth"] = 1.5
      mpl.rcParams["lines.markeredgewidth"] = 3.0
      mpl.rcParams["lines.markersize"] = 3.0
      # mpl.rcParams['font.sans-serif'] = 'Droid Sans'
  
      # mpl.rcParams['font.family'] = 'Open Sans'
      # mpl.rcParams['font.weight'] = 400
      mpl.rcParams['mathtext.default'] = 'regular'
  
      # mpl.rcParams['font.family'] = 'Droid Sans'
  
      mpl.rcParams['text.usetex'] = False
  
      mpl.rc(
          'text.latex',
          preamble=''.join((
              # r'\usepackage{droidsans}',
              # r'\usepackage[T1]{fontenc} ',
              r'\usepackage{sfmath} \renewcommand{\rmfamily}{\sffamily}',
              r'\renewcommand\familydefault{\sfdefault} ',
              # r'\usepackage{mathastext} '
          ))
      )