text: """A functions module, includes all the standard functions.
  
  Combinatorial - factorial, fibonacci, harmonic, bernoulli...
  Elementary - hyperbolic, trigonometric, exponential, floor and ceiling, sqrt...
  Special - gamma, zeta,spherical harmonics...
  """
  
  from sympy.functions.combinatorial.factorials import (factorial, factorial2,
          rf, ff, binomial, RisingFactorial, FallingFactorial, subfactorial)
  from sympy.functions.combinatorial.numbers import (fibonacci, lucas, harmonic,
          bernoulli, bell, euler, catalan, genocchi)
  from sympy.functions.elementary.miscellaneous import (sqrt, root, Min, Max,
          Id, real_root, cbrt)
  from sympy.functions.elementary.complexes import (re, im, sign, Abs,
          conjugate, arg, polar_lift, periodic_argument, unbranched_argument,
          principal_branch, transpose, adjoint, polarify, unpolarify)
  from sympy.functions.elementary.trigonometric import (sin, cos, tan,
          sec, csc, cot, sinc, asin, acos, atan, asec, acsc, acot, atan2)
  from sympy.functions.elementary.exponential import (exp_polar, exp, log,
          LambertW)
  from sympy.functions.elementary.hyperbolic import (sinh, cosh, tanh, coth,
          sech, csch, asinh, acosh, atanh, acoth, asech)
  from sympy.functions.elementary.integers import floor, ceiling, frac
  from sympy.functions.elementary.piecewise import Piecewise, piecewise_fold
  from sympy.functions.special.error_functions import (erf, erfc, erfi, erf2,
          erfinv, erfcinv, erf2inv, Ei, expint, E1, li, Li, Si, Ci, Shi, Chi,
          fresnels, fresnelc)
  from sympy.functions.special.gamma_functions import (gamma, lowergamma,
          uppergamma, polygamma, loggamma, digamma, trigamma)
  from sympy.functions.special.zeta_functions import (dirichlet_eta, zeta,
          lerchphi, polylog, stieltjes)
  from sympy.functions.special.tensor_functions import (Eijk, LeviCivita,
          KroneckerDelta)
  from sympy.functions.special.delta_functions import DiracDelta, Heaviside
  from sympy.functions.special.bsplines import bspline_basis, bspline_basis_set
  from sympy.functions.special.bessel import (besselj, bessely, besseli, besselk,
          hankel1, hankel2, jn, yn, jn_zeros, hn1, hn2, airyai, airybi, airyaiprime, airybiprime)
  from sympy.functions.special.hyper import hyper, meijerg
  from sympy.functions.special.polynomials import (legendre, assoc_legendre,
          hermite, chebyshevt, chebyshevu, chebyshevu_root, chebyshevt_root,
          laguerre, assoc_laguerre, gegenbauer, jacobi, jacobi_normalized)
  from sympy.functions.special.spherical_harmonics import Ynm, Ynm_c, Znm
  from sympy.functions.special.elliptic_integrals import (elliptic_k,
          elliptic_f, elliptic_e, elliptic_pi)
  from sympy.functions.special.beta_functions import beta
  from sympy.functions.special.mathieu_functions import (mathieus, mathieuc,
          mathieusprime, mathieucprime)
  ln = log
  