input: Write a function to generate a voltage signal with random noise using a Python script. The function should take the frequency and amplitude of the signal as inputs and return the noisy voltage signal.
  
  import numpy as np
  
  def generate_noisy_signal(freq, amplitude):
      t = np.linspace(0, 1, 1000)
      voltage_signal = amplitude * np.sin(2 * np.pi * freq * t) + np.random.normal(0, 0.1, 1000)
      return voltage_signal
  
  assert np.array_equal(generate_noisy_signal(250, 1).shape, (1000,))
  assert np.all(np.abs(np.mean(generate_noisy_signal(250, 1))) < 0.1)
  assert np.abs(np.max(generate_noisy_signal(250, 1)) - 1.1) < 0.2
  assert np.abs(np.min(generate_noisy_signal(250, 1)) + 1.1) < 0.2
output: def generate_noisy_signal(freq, amplitude):
      t = np.linspace(0, 1, 1000)
      voltage_signal = amplitude * np.sin(2 * np.pi * freq * t) + np.random.normal(0, 0.1, 1000)
      return voltage_signal