class_docstr: Unit tests for the ``rect`` function.
class_docstr_tok: ["Unit","tests","for","the","``","rect","``","function","."]
docstr: Test that the ``rect`` convenience function returns a callable with two arguments
  corresponding to the trainable parameters and time.
docstr_tok: ["Test","that","the","``","rect","``","convenience","function","returns","a","callable","with","two","arguments","corresponding","to","the","trainable","parameters","and","time","."]
code: def test_rect_returns_callable(self):
      """Test that the ``rect`` convenience function returns a callable with two arguments
      corresponding to the trainable parameters and time."""
      c = qml.pulse.rect(
          x=10, windows=[0, 10]
      )  # return 10 when time is between 0 and 10
      argspec = inspect.getfullargspec(c)
  
      assert callable(c)
      assert argspec.args == ["p", "t"]
  
imports: import inspect
  from functools import reduce
  import numpy
  import pytest
  import pennylane
  from pennylane.pulse import ParametrizedHamiltonian
label_desc: Use image node_id 1 for calling the TestRect obj's underlying member method code with example usage: obj.test_rect_returns_callable() without return types