def bondprice(ytm, period, par, coupon):
  price_bond = par*coupon/2*(1-(1+ytm/2)**(-2*period))/(ytm/2) + par/(1+ytm/2)**(2*period)
  return price_bond

# create a list of YTMs from 0.01 to 0.50
ytm_list = [x/100 for x in range(1, 51)]

print(ytm_list)

# create a list of bond prices
output = []
for element in ytm_list:
  output.append(bondprice(ytm=element, period=50, par=1000, coupon=0.10))

print(output)

from matplotlib import pyplot as plt
plt.plot(ytm_list, output)
plt.show()