title: Sympy calculation of division
body: <p>I'm trying to do some math with sympy, but I don't seem to figure out how to support division:</p>
  <pre><code>from sympy import Symbol, lambdify
  
  
  a = Symbol('a')
  b = Symbol('b')
  c = a * b
  lambdified = lambdify(c.args, c)
  value = lambdified(a=2, b=3)
  print(value)
  
  
  x = Symbol('x')
  y = Symbol('y')
  z = x / y
  lambdified_2 = lambdify(z.args, z)
  value_2 = lambdified_2(x=2, y=3)
  print(value_2)
  </code></pre>
  <p>This returns:</p>
  <pre><code>    def _lambdifygenerated(x, 1/y):
                            ^
  SyntaxError: invalid syntax
  </code></pre>
  <p>I tried to fix this by passing <code>free_symbols</code> instead, this works but raises the error:</p>
  <pre><code>x = Symbol('x')
  y = Symbol('y')
  z = x / y
  lambdified_2 = lambdify(z.free_symbols, z)
  value_2 = lambdified_2(x=2, y=3)
  print(value_2)
  </code></pre>
  <p>returning</p>
  <pre><code>SymPyDeprecationWarning: 
  
  Passing the function arguments to lambdify() as a set is deprecated. This
  leads to unpredictable results since sets are unordered. Instead, use a list
  or tuple for the function arguments.
  </code></pre>
  <p>Now, I could fix this by casting <code>z.free_symbols</code> to a tuple, but I'm sure there's a better way of doing this. How should I pass the arguments?</p>
  <hr />
  <p>To be clear, I don't want to pass <code>[x,y]</code> in the args because I want to only have to pass the equation later on.</p>