input: 
  def generate_voltage_signal(frequency: float, amplitude: float, duration: float, sample_rate: int) -> np.ndarray:
      """Generate a voltage signal with random noise based on the given frequency and amplitude.
      The signal is generated for the specified duration and sampled at the given rate.
      >>> generate_voltage_signal(250, 1, 1, 1000)
      A signal with frequency of 250 Hz, amplitude of 1 V, and random noise.
      """
  
output:     import numpy as np
      t = np.linspace(0, duration, int(duration * sample_rate), endpoint=False)
      signal = amplitude * np.sin(2 * np.pi * frequency * t)
      noise = np.random.normal(0, 0.1, len(t))
      return signal + noise