input: def perform_linear_regression(X, Y):
      """ Perform linear regression to predict the numbers in a given dataset.
      >>> X = [1,2,3,4,5]
      >>> Y = [3,5,7,9,13]
      >>> perform_linear_regression(X, Y)
      [15.0]
      """
      import numpy as np
      from sklearn.linear_model import LinearRegression
  
      X = np.array(X).reshape(-1,1)
      Y = np.array(Y)
  
      model = LinearRegression()
      model.fit(X, Y)
  
      # Predicts the value of y
      return model.predict([[7]])
output:     import numpy as np
      from sklearn.linear_model import LinearRegression
  
      X = np.array(X).reshape(-1,1)
      Y = np.array(Y)
  
      model = LinearRegression()
      model.fit(X, Y)
  
      # Predicts the value of y
      return model.predict([[7]])