title: I tried to check probability of some occurrence in sympy stats. Didn't work
body: <p>I ran this and it is trying to compute for hours. Did I do sth wrong?</p>
  <pre><code>from sympy import *
  from sympy.stats import P
  from sympy.stats import Normal
  
  m1,m2,s1,s2 = symbols('\mu_1, \mu_2, \sigma_1, \sigma_2')
  
  x1 = Normal('x_1', m1, s1)
  x2 = Normal('x_2', m2, s2)
    
  P(x1&gt;x2)
  </code></pre>