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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def SAS_NG(self):
 """ Set-up for the ungridded superposition of analytical solutions method for solving flexure """

    if self.filename:
      # Define the (scalar) elastic thickness
      self.Te = self.configGet("float", "input", "ElasticThickness")
      # See if it wants to be run in lat/lon
      # Could put under in 2D if-statement, but could imagine an eventual desire
      # to change this and have 1D lat/lon profiles as well.
      # So while the options will be under "numerical2D", this place here will 
      # remain held for an eventual future.
      self.latlon = self.configGet("string", "numerical2D", "latlon", optional=True)
      self.PlanetaryRadius = self.configGet("float", "numerical2D", "PlanetaryRadius", optional=True)
      if self.dimension == 2:
        from scipy.special import kei
    # Parse out input q0 into variables of imoprtance for solution
    if self.dimension == 1:
      try:
        # If these have already been set, e.g., by getters/setters, great!
        self.x
        self.q
      except:
        # Using [x, y, w] configuration file
        if self.q0.shape[1] == 2:
          self.x = self.q0[:,0]
          self.q = self.q0[:,1]
        else:
          sys.exit("For 1D (ungridded) SAS_NG configuration file, need [x,w] array. Your dimensions are: "+str(self.q0.shape))
    else:
      try:
        # If these have already been set, e.g., by getters/setters, great!
        self.x
        self.u
        self.q
      except:
        # Using [x, y, w] configuration file
        if self.q0.shape[1] == 3:
          self.x = self.q0[:,0]
          self.y = self.q0[:,1]
          self.q = self.q0[:,2]
        else:
          sys.exit("For 2D (ungridded) SAS_NG configuration file, need [x,y,w] array. Your dimensions are: "+str(self.q0.shape))
    # x, y are in absolute coordinates. Create a local grid reference to 
    # these. This local grid, which starts at (0,0), is defined just so that 
    # we have a way of running the model without defined real-world 
    # coordinates
    self.x = self.x
    if self.dimension == 2:
      self.y = self.y
    # Remove self.q0 to avoid issues with multiply-defined inputs
    # q0 is the parsable input to either a qs grid or contains (x,(y),q)
    del self.q0
    
    # Check if a seperate output set of x,y points has been defined
    # otherwise, set those values to None
    # First, try to load the arrays
    try:
      self.xw
    except:
      try:
        self.xw = self.configGet('string', "input", "xw", optional=True)
        if self.xw == '':
          self.xw = None
      except:
        self.xw = None
    # If strings, load arrays
    if type(self.xw) == str:
      self.xw = self.loadFile(self.xw)
    if self.dimension == 2:
      try:
        # already set by setter?
        self.yw
      except:
        try:
          self.yw = self.configGet('string', "input", "yw", optional=True )
          if self.yw == '':
            self.yw = None
        except:
          self.yw = None
      # At this point, can check if we have both None or both defined
      if (self.xw is not None and self.yw is None) \
        or (self.xw is None and self.yw is not None):
        sys.exit("SAS_NG output at specified points requires both xw and yw to be defined")
      # All right, now just finish defining
      if type(self.yw) == str:
        self.yw = self.loadFile(self.yw)
      elif self.yw is None:
        self.yw = self.y.copy()
    if self.xw is None:
      self.xw = self.x.copy()