from statistics import mean, stdev
import matplotlib
import numpy as np
import matplotlib.pyplot as plt

obsList = [3.7, 4.2, 4.4, 4.4, 4.3, 4.2, 4.4, 4.8, 4.9, 4.4,
       4.2, 3.8, 4.2, 4.4, 4.6, 3.9, 4.3, 4.5, 4.8, 3.9,
       4.7, 4.2, 4.2, 4.8, 4.5, 3.6, 4.1, 4.3, 3.9, 4.2,
       4.0, 4.2, 4.0, 4.5, 4.4, 4.1, 4.0, 4.0, 3.8, 4.6,
       4.9, 3.8, 4.3, 4.3, 3.9, 3.8, 4.7, 3.9, 4.0, 4.2,
       4.3, 4.7, 4.1, 4.0, 4.6, 4.4, 4.6, 4.4, 4.9, 4.4,
       4.0, 3.9, 4.5, 4.3, 3.8, 4.1, 4.3, 4.2, 4.5, 4.4,
       4.2, 4.7, 3.8, 4.5, 4.0, 4.2, 4.1, 4.0, 4.7, 4.1,
       4.7, 4.1, 4.8, 4.1, 4.3, 4.7, 4.2, 4.1, 4.4, 4.8,
       4.1, 4.9, 4.3, 4.4, 4.4, 4.3, 4.6, 4.5, 4.6, 4.0]
xBar = mean(obsList)
stdDev = stdev(obsList)
fig, ax = plt.subplots()
n,bins,patches = ax.hist(obsList,bins="auto",density=True)
y = ((1 / (np.sqrt(2 * np.pi) * stdDev)) *
     np.exp(-0.5 * (1 / stdDev * (bins - xBar))**2))
ax.plot(bins,y,"--")
ax.set_xlabel("Weight - grams")
ax.set_ylabel("Probability")
fig.tight_layout()
plt.show()'