old_contents: from lcapy import Vdc, R, L, C
  import numpy as np
  from matplotlib.pyplot import figure, savefig, show
  
  a = (Vdc(5) + R(10)) | C(1)
  
  t = np.linspace(0, 10, 1000)
  
  fig = figure()
  ax = fig.add_subplot(111)
  ax.plot(t, a.V.impulse_response(t), linewidth=2)
  ax.set_xlabel('Time (s)')
  ax.set_ylabel('Voltage (V)')
  ax.grid(True)
  
  show()
  
new_contents: from lcapy import Vstep, R, L, C
  import numpy as np
  from matplotlib.pyplot import figure, savefig, show
  
  a = (Vstep(5) + R(10)) | C(1)
  
  t = np.linspace(0, 10, 1000)
  
  fig = figure()
  ax = fig.add_subplot(111)
  ax.plot(t, a.v.evaluate(t), linewidth=2)
  ax.set_xlabel('Time (s)')
  ax.set_ylabel('Voltage (V)')
  ax.grid(True)
  
  show()
  
subject: Fix time response