-- Sources
   |--__init__.py
   |--Calculators
      |--__init__.py
      |--Filters.py
   |--Controllers
      |--__init__.py
      |--FiltersController.py
   |--Viewers
      |--__init__.py
      |--DataVisualization.py
   |--Models
      |--__init__.py
      |--Data

import Sources.Models.Data as Dt

import Sources.Calculators.Filters as Fs
import Sources.Models.Data as Dt

import Calculators.Filters as Fs
import Controllers.FiltersController as Fc
import Models.Data as Dt
import Viewers.DataVisualization as Dv

Traceback (most recent call last):
  File "__init__.py", line 10, in <module>
    import Calculators.Filters as Fs
  File "/Users/paulaceccon/PycharmProjects/UncertaintyQuantificationOfFilters/Sources/Calculators/Filters.py", line 6, in <module>
    import Sources.Models.Data as Dt
ImportError: No module named Sources.Models.Data

package = os.path.dirname(os.path.dirname(os.path.realpath(__file__)))
sys.path.append(package)