Added "import numpy as np" statement to filter examples (#16351)
Added "import numpy as np" statement to filter examples (#16351)

* Added "import numpy as np" statement to examples

Noticed examples were missing a numpy import, and fail when copy-pasted and numpy is not already imported. Fixed all examples.
ilayn/scipy,andyfaff/scipy,anntzer/scipy,WarrenWeckesser/scipy,Stefan-Endres/scipy,scipy/scipy,perimosocordiae/scipy,anntzer/scipy,andyfaff/scipy,rgommers/scipy,scipy/scipy,mdhaber/scipy,perimosocordiae/scipy,anntzer/scipy,andyfaff/scipy,anntzer/scipy,mdhaber/scipy,WarrenWeckesser/scipy,rgommers/scipy,endolith/scipy,andyfaff/scipy,mdhaber/scipy,perimosocordiae/scipy,ilayn/scipy,rgommers/scipy,Stefan-Endres/scipy,anntzer/scipy,scipy/scipy,Stefan-Endres/scipy,perimosocordiae/scipy,Stefan-Endres/scipy,ilayn/scipy,mdhaber/scipy,mdhaber/scipy,endolith/scipy,perimosocordiae/scipy,andyfaff/scipy,scipy/scipy,perimosocordiae/scipy,Stefan-Endres/scipy,scipy/scipy,rgommers/scipy,WarrenWeckesser/scipy,ilayn/scipy,WarrenWeckesser/scipy,andyfaff/scipy,rgommers/scipy,endolith/scipy,endolith/scipy,endolith/scipy,WarrenWeckesser/scipy,Stefan-Endres/scipy,WarrenWeckesser/scipy,ilayn/scipy,mdhaber/scipy,scipy/scipy,endolith/scipy,ilayn/scipy,anntzer/scipy