from ete3 import Tree
#Loads a tree
t = Tree( '((H:1,I:1):0.5, A:1, (B:1,(C:1,D:1):0.5):0.5);' )
print(t)
#                    /-H
#          /--------|
#         |          \-I
#         |
#---------|--A
#         |
#         |          /-B
#          \--------|
#                   |          /-C
#                    \--------|
#                              \-D
# I get D
D = t.search_nodes(name="D")
# I get all nodes with distance=0.5
nodes = t.search_nodes(dist=0.5)
print(len(nodes), "nodes have distance=0.5")