import proveit
# Automation is not needed when building an expression:
proveit.defaults.automation = False # This will speed things up.
proveit.defaults.inline_pngs = False # Makes files smaller.
%load_expr # Load the stored expression as 'stored_expr'
# import Expression classes needed to build the expression
from proveit import Conditional, Lambda, a, b, c, d, e
from proveit.logic import And, Equals, Forall, InSet
from proveit.numbers import Complex, ComplexNonZero, Mult, frac
# build up the expression from sub-expressions
expr = Lambda([a, d], Conditional(Forall(instance_param_or_params = [b, c, e], instance_expr = Equals(Mult(frac(Mult(a, b), c), frac(d, Mult(b, e))), Mult(frac(a, c), frac(d, e))), domain = ComplexNonZero), And(InSet(a, Complex), InSet(d, Complex))))
# check that the built expression is the same as the stored expression
assert expr == stored_expr
assert expr._style_id == stored_expr._style_id
print("Passed sanity check: expr matches stored_expr")
# Show the LaTeX representation of the expression for convenience if you need it.
print(stored_expr.latex())
stored_expr.style_options()
# display the expression information
stored_expr.expr_info()