input: 
  import numpy as np
  
  def generate_voltage_signal(frequency: float, amplitude: float, duration: float, sampling_rate: int, noise_std: float) -> np.ndarray:
      """ Generate a voltage signal with random noise based on the given parameters.
      The signal is a sine wave with the specified frequency and amplitude, and it includes
      Gaussian noise with the specified standard deviation.
  
      >>> generate_voltage_signal(250, 1, 1, 1000, 0.1)
      array([ 0.9505,  0.0926, -0.3130, ..., -1.3693,  1.2950,  0.2503])
      """
      t = np.linspace(0, duration, sampling_rate * duration)
      voltage_signal = amplitude * np.sin(2 * np.pi * frequency * t) + np.random.normal(0, noise_std, sampling_rate * duration)
      return voltage_signal
  
output:     t = np.linspace(0, duration, sampling_rate * duration)
      voltage_signal = amplitude * np.sin(2 * np.pi * frequency * t) + np.random.normal(0, noise_std, sampling_rate * duration)
      return voltage_signal