message: bug in Python SimplexTree (needs string)
  Doc issue in alpha_complex user doc
diff: @@ -2,6 +2,7 @@ from cython cimport numeric
  from libcpp.vector cimport vector
  from libcpp.utility cimport pair
  from libcpp cimport bool
  +from libcpp.string cimport string
  """This file is part of the Gudhi Library. The Gudhi library
  (Geometric Understanding in Higher Dimensions) is a generic C++
  