text: from .electrolyte_base_Landesfeind2019 import electrolyte_TDF_base_Landesfeind2019
  import numpy as np
  
  
  def electrolyte_TDF_EC_EMC_3_7_Landesfeind2019(c_e, T):
      """
      Thermodynamic factor (TDF) of LiPF6 in EC:EMC (3:7 w:w) as a function of ion
      concentration and temperature. The data comes from [1].
  
      References
      ----------
      .. [1] Landesfeind, J. and Gasteiger, H.A., 2019. Temperature and Concentration
      Dependence of the Ionic Transport Properties of Lithium-Ion Battery Electrolytes.
      Journal of The Electrochemical Society, 166(14), pp.A3079-A3097.
  
      Parameters
      ----------
      c_e: :class:`pybamm.Symbol`
          Dimensional electrolyte concentration
      T: :class:`pybamm.Symbol`
          Dimensional temperature
  
      Returns
      -------
      :class:`pybamm.Symbol`
          Electrolyte thermodynamic factor
      """
      coeffs = np.array(
          [2.57e1, -4.51e1, -1.77e-1, 1.94, 2.95e-1, 3.08e-4, 2.59e-1, -9.46e-3, -4.54e-4]
      )
  
      return electrolyte_TDF_base_Landesfeind2019(c_e, T, coeffs)
  