code: def square(x):
      return x**2
  
file_path: sympy/sympy/strategies/tests/test_tree.py
imports: from sympy.strategies.tree import treeapply, greedy, allresults, brute
  from functools import partial, reduce
label_desc: Use image node_id 4 for calling a global function with example usage: square(x) and returns: unknown