old_contents: """Some calculus-related methods waiting to find a better place in the
  SymPy modules tree.
  """
  
  from .euler import euler_equations
  from .singularities import (singularities, is_increasing,
                              is_strictly_increasing, is_decreasing,
                              is_strictly_decreasing, is_monotonic)
  from .finite_diff import finite_diff_weights, apply_finite_diff, as_finite_diff
  from .util import not_empty_in, AccumBounds
  
new_contents: """Some calculus-related methods waiting to find a better place in the
  SymPy modules tree.
  """
  
  from .euler import euler_equations
  from .singularities import (singularities, is_increasing,
                              is_strictly_increasing, is_decreasing,
                              is_strictly_decreasing, is_monotonic)
  from .finite_diff import finite_diff_weights, apply_finite_diff, as_finite_diff
  from .util import not_empty_in, AccumBounds
  
  
  __all__ = [
  'euler_equations',
  
  'singularities', 'is_increasing',
  'is_strictly_increasing', 'is_decreasing',
  'is_strictly_decreasing', 'is_monotonic',
  
  'finite_diff_weights', 'apply_finite_diff', 'as_finite_diff',
  
  'not_empty_in', 'AccumBounds',
  ]
  
subject: Add __all__ to sympy/calculus/__init__.py