old_contents: """
  A collection of common constants and forcefield parameters
  """
  
  radians_to_degrees = 57.29577951308232  # 180/pi
  degrees_to_radians = 0.017453292519943295 # pi/180
  
  
  """
  C: carbonyl carbon
  CR: carbon with no hydrogens,
  CR1E: extended aromatic carbon with 1 H
  CH1E: extended aliphatic carbon with 1 H
  CH2E: extended aliphatic carbon with 2 H
  CH3E: extended aliphatic carbon with 3 H
  NH1: amide nitrogen
  NR: aromatic nitrogen with no hydrogens
  NH2: nitrogen bound to two hydrogens
  NH3: nitrogen bound to three hydrogens
  NC2: guanidinium nitrogen
  N: proline nitrogen
  OH1: hydroxyl oxygen
  O: carbonyl oxygen
  OC: carboxyl oxygen
  S: sulphur
  SH1E: extended sulphur with one hydrogen
  H?: this entry seems to be an hydrogen
  H?: this entry seems to be an hydrogen
  
  see table I Effective Energy Function for Proteins in Solution 
  Themis Lazaridis and Martin Karplus
  
  """
  
  # Lennard parameters
  lj_sigma = [2.100, 2.100, 2.365, 2.235, 2.165, 2.100, 1.6000, 1.6000, 1.6000,
   1.6000, 1.6000, 1.6000, 1.6000, 1.6000, 1.6000,  1.890, 1.890, 0.8000, 0.6000]
   
  lj_epsilon = [-0.1200, -0.1200, -0.0486, -0.1142, -0.1811, -0.1200, -0.2384,
   -0.2384, -0.2384, -0.2384, -0.2384, -0.2384, -0.1591, -0.1591, -0.6469, 
   -0.0430, -0.0430, -0.0498, -0.0498]
  
  
  
  
  
  
new_contents: """
  A collection of common constants and forcefield parameters
  """
  from collections import namedtuple
  Constants = namedtuple('Constants', ['radians_to_degrees', 'degrees_to_radians', 'pi'])
  constants = Constants(
      57.29577951308232, 0.017453292519943295, 3.141592653589793)
  
  
  """
  C: carbonyl carbon
  CR: carbon with no hydrogens,
  CR1E: extended aromatic carbon with 1 H
  CH1E: extended aliphatic carbon with 1 H
  CH2E: extended aliphatic carbon with 2 H
  CH3E: extended aliphatic carbon with 3 H
  NH1: amide nitrogen
  NR: aromatic nitrogen with no hydrogens
  NH2: nitrogen bound to two hydrogens
  NH3: nitrogen bound to three hydrogens
  NC2: guanidinium nitrogen
  N: proline nitrogen
  OH1: hydroxyl oxygen
  O: carbonyl oxygen
  OC: carboxyl oxygen
  S: sulphur
  SH1E: extended sulphur with one hydrogen
  H?: this entry seems to be an hydrogen
  H?: this entry seems to be an hydrogen
  
  see table I Effective Energy Function for Proteins in Solution 
  Themis Lazaridis and Martin Karplus
  
  """
  
  # Lennard parameters
  lj_sigma = [2.100, 2.100, 2.365, 2.235, 2.165, 2.100, 1.6000, 1.6000, 1.6000,
              1.6000, 1.6000, 1.6000, 1.6000, 1.6000, 1.6000,  1.890, 1.890, 0.8000, 0.6000]
  
  lj_epsilon = [-0.1200, -0.1200, -0.0486, -0.1142, -0.1811, -0.1200, -0.2384,
                -0.2384, -0.2384, -0.2384, -0.2384, -0.2384, -0.1591, -0.1591, -0.6469,
                -0.0430, -0.0430, -0.0498, -0.0498]
  
subject: add namedtuple