input: Write a function to perform a series of calculations and generate plots based on input data. Before running the script, ensure to run eval_spectrum.py and calibration.py with appropriate measurements. The function should import necessary modules and functions from external sources. It should load the input data, perform calibration, calculate various values, and generate plots based on instructions provided in a separate text file. The plots should show absorbed power vs emitted power, absorbed power vs reflectivity, and dissipated power vs wavelength, and also display the calculated thermal resistance on the plot. If the input data is empty, the function should return a message indicating that no data was provided.
  
  
  def perform_calculations_and_plots(logfile, calib_folder, instrfile):
      if logfile is None or calib_folder is None or instrfile is None:
          return "No data provided"
      
      # Import necessary modules and functions
      import numpy as np
      import matplotlib.pyplot as plt
      import errorvalues as ev
      from VECSELsetup.eval.varycolor import varycolor
      from VECSELsetup.eval.gen_functions import load, extract, plotinstructions_write, plotinstructions_read, lut_from_calibfolder, lut_interp_from_calibfolder, thermal_resistance
      
      # Load and process the input data
      current_set, current, pump, refl, laser, spectra, meantemp = ..., ..., ..., ..., ..., ..., ...
      Temperatures = sorted(current_set.keys())
      T_out = {(T, meantemp[T].round(1)) for T in Temperatures}
      
      # Perform calibration
      emis_lut = lut_from_calibfolder(calib_folder, identifiers=['Laser'], ignore_error=False)
      pump_lut, refl_lut = lut_interp_from_calibfolder(calib_folder, identifiers=['Pump', 'Refl'])
      
      # Calculate various values
      absorbed, reflected, emitted, pumped, dissipated = ..., ..., ..., ..., ...
      for T in Temperatures:
          reflected[T] = refl_lut(refl[T])
          pumped[T] = pump_lut(pump[T])
          absorbed[T] = pumped[T] - reflected[T]
          emitted[T] = emis_lut(laser[T])
          dissipated[T] = absorbed[T] - emitted[T]
      
      # Generate plots based on instructions
      plotinstructions_write(instrfile, Temperatures, calib_folder)
      instr = plotinstructions_read(instrfile)
      
      # Plotting
      plt.figure(figsize=(15, 10))
      plt.subplot(3, 1, 1)
      for T in Temperatures:
          plt.errorbar(absorbed[T].v(), emitted[T].v(), xerr=absorbed[T].e(), yerr=emitted[T].e(), ...)
          plt.plot(absorbed[T].v(), ..., ...)
      
      plt.subplot(3, 1, 2)
      for T in Temperatures:
          relref = reflected[T] / pumped[T] * 100
          plt.errorbar(absorbed[T].v(), relref.v(), xerr=absorbed[T].e(), yerr=relref.e(), ...)
      
      plt.subplot(3, 1, 3)
      for T in Temperatures:
          if T in plot_temps_for_3:
              plt.errorbar(dissipated[T].v(), spectra[T][1].v(), xerr=dissipated[T].e(), yerr=spectra[T][1].e(), ...)
      
      # Calculate thermal resistance
      wavelength, slopes, T_active = ..., ..., ...
      dldD, dldT, l0 = thermal_resistance(T_active, wavelength, slopes)
      R_th = dldD / dldT
      
      # Display thermal resistance on the plot
      plt.text(textx3, texty3[0], ...)
      therm_imp = f"Thermal impedance: ({R_th.round(2)}) K/W"
      plt.text(textx3, texty3[1], therm_imp, color='k')
      
      plt.show()
  
  # Test cases
  assert perform_calculations_and_plots(None, None, None) == "No data provided"
  assert perform_calculations_and_plots(logfile, calib_folder, instrfile) != "No data provided"
  
output: def perform_calculations_and_plots(logfile, calib_folder, instrfile):
      if logfile is None or calib_folder is None or instrfile is None:
          return "No data provided"
      
      import numpy as np
      import matplotlib.pyplot as plt
      import errorvalues as ev
      from VECSELsetup.eval.varycolor import varycolor
      from VECSELsetup.eval.gen_functions import load, extract, plotinstructions_write, plotinstructions_read, lut_from_calibfolder, lut_interp_from_calibfolder, thermal_resistance
      
      current_set, current, pump, refl, laser, spectra, meantemp = load(logfile)
      Temperatures = sorted(current_set.keys())
      T_out = {(T, meantemp[T].round(1)) for T in Temperatures}
      
      emis_lut = lut_from_calibfolder(calib_folder, identifiers=['Laser'], ignore_error=False)
      pump_lut, refl_lut = lut_interp_from_calibfolder(calib_folder, identifiers=['Pump', 'Refl'])
      
      absorbed, reflected, emitted, pumped, dissipated = {}, {}, {}, {}, {}
      for T in Temperatures:
          reflected[T] = refl_lut(refl[T])
          pumped[T] = pump_lut(pump[T])
          absorbed[T] = pumped[T] - reflected[T]
          emitted[T] = emis_lut(laser[T])
          dissipated[T] = absorbed[T] - emitted[T]
      
      plotinstructions_write(instrfile, Temperatures, calib_folder)
      instr = plotinstructions_read(instrfile)
      
      plt.figure(figsize=(15, 10))
      plt.subplot(3, 1, 1)
      for T in Temperatures:
          plt.errorbar(absorbed[T].v(), emitted[T].v(), xerr=absorbed[T].e(), yerr=emitted[T].e(), fmt='o')
          plt.plot(absorbed[T].v(), emitted[T].v(), label=f'T={T}')
      plt.xlabel('Absorbed Power')
      plt.ylabel('Emitted Power')
      plt.legend()
      
      plt.subplot(3, 1, 2)
      for T in Temperatures:
          relref = reflected[T] / pumped[T] * 100
          plt.errorbar(absorbed[T].v(), relref.v(), xerr=absorbed[T].e(), yerr=relref.e(), fmt='o')
      plt.xlabel('Absorbed Power')
      plt.ylabel('Reflectivity (%)')
      
      plt.subplot(3, 1, 3)
      plot_temps_for_3 = instr['plot_temps_for_3']
      for T in Temperatures:
          if T in plot_temps_for_3:
              plt.errorbar(dissipated[T].v(), spectra[T][1].v(), xerr=dissipated[T].e(), yerr=spectra[T][1].e(), fmt='o')
      plt.xlabel('Dissipated Power')
      plt.ylabel('Wavelength')
      
      wavelength, slopes, T_active = instr['wavelength'], instr['slopes'], instr['T_active']
      dldD, dldT, l0 = thermal_resistance(T_active, wavelength, slopes)
      R_th = dldD / dldT
      
      textx3, texty3 = instr['textx3'], instr['texty3']
      plt.text(textx3, texty3[0], f'Thermal impedance: {R_th.round(2)} K/W', color='k')
      
      plt.show()