code: def test_formula_property():
      # Check that you can create a Formula with one term
      t1 = F.Term("x")
      f = t1.formula
      assert f.design_expr == [t1]
  
imports: from warnings import catch_warnings, simplefilter
  import numpy
  import pytest
  import sympy
  from numpy.core.records import fromrecords
  from numpy.testing import assert_almost_equal, assert_array_equal
  from sympy.utilities.lambdify import implemented_function
  from nipy.utils import VisibleDeprecationWarning
  from ..None import formulae
  from ..formulae import Term, terms
label_desc: Use image node_id 8 for calling a global function with example usage: test_formula_property() without return types