code: def eeg_create_frequency_bands(bands="all", step=1):
      
      if bands == "all" or bands == "All":
          bands = ["Delta", "Theta", "Alpha", "Beta", "Gamma", "Mu"]
      if "Alpha" in bands:
          bands.remove("Alpha")
          bands += ["Alpha1", "Alpha2"]
      if "Beta" in bands:
          bands.remove("Beta")
          bands += ["Beta1", "Beta2"]
      if "Gamma" in bands:
          bands.remove("Gamma")
          bands += ["Gamma1", "Gamma2"]
  
      frequencies = {}
      for band in bands:
          if band == "Delta":
              frequencies[band] = np.arange(1, 3+0.1, step)
          if band == "Theta":
              frequencies[band] = np.arange(4, 7+0.1, step)
          if band == "Alpha1":
              frequencies[band] = np.arange(8, 9+0.1, step)
          if band == "Alpha2":
              frequencies[band] = np.arange(10, 12+0.1, step)
          if band == "Beta1":
              frequencies[band] = np.arange(13, 17+0.1, step)
          if band == "Beta2":
              frequencies[band] = np.arange(18, 30+0.1, step)
          if band == "Gamma1":
              frequencies[band] = np.arange(31, 40+0.1, step)
          if band == "Gamma2":
              frequencies[band] = np.arange(41, 50+0.1, step)
          if band == "Mu":
              frequencies[band] = np.arange(8, 13+0.1, step)
      return(frequencies)
docs: Delta: 1-3Hz
      Theta: 4-7Hz
      Alpha1: 8-9Hz
      Alpha2: 10-12Hz
      Beta1: 13-17Hz
      Beta2: 18-30Hz
      Gamma1: 31-40Hz
      Gamma2: 41-50Hz
      Mu: 8-13Hz