def test_contains()-> None:
x = SimplePrefixTree('Sum')
y = SimplePrefixTree('Sum')
z = SimplePrefixTree('Sum')
z.value = 'a'
z.weight = 1
y.subtrees = [z]
y.weight = 1
y.value = ['a']
x.subtrees = [y]
x.weight = 1
x.value = []
assert (['a'] in x) == True
assert ([] in x) == True
assert (['b'] in x) == False
assert ([1] in x) == False
def test_len() -> None:
"""
"""
x = SimplePrefixTree('Sum')
y = SimplePrefixTree('Sum')
y.value = 3
y.weight = 1
x.subtrees = [y]
x.weight = 1
assert len(x) == 1
x = SimplePrefixTree('Sum')
y = SimplePrefixTree('Sum')
z = SimplePrefixTree('Sum')
z.value = 'a'
z.weight = 1
y.subtrees = [z]
y.weight = 1
y.value = ['a']
x.subtrees = [y]
x.weight = 1
x.value = []
assert len(x) == 1
x = SimplePrefixTree('Sum')
y = SimplePrefixTree('Sum')
z = SimplePrefixTree('Sum')
z.value = 'a'
z.weight = 1
y.subtrees = [z]
y.weight = 1
y.value = ['a']
x.subtrees = [y]
x.weight = 1
x.value = []
assert len(x) == 1
