lazy evaluation

Execution

$ python test1.py
{'id': 3}
{'id': 3}

$ python test2.py
{'id': 2}
{'id': 3}

why different??

module.py

module_var = {
	'id': None
}

test1.py

from module import module_var

class child(object):
	def __init__(self, var=None):
		self.child_var = module_var
		if var:
			self.child_var['id'] = var
	def update(self, new_var):
		self.child_var['id'] = new_var
	def get(self):
		return self.child_var

class parent(object):
	def __init__(self):
		self.child_records = {}
	def new(self, name, var):
		record = child(var)
		self.child_records[name] = record
	def get(self, name):
		return self.child_records.get(name)

p = parent()

p.new('A', 2)
p.new('B', 3)

print(p.get('A').get())
print(p.get('B').get())

test2.py

from module import module_var

class child(object):
	def __init__(self, var=None):
		#self.child_var = module_var
		self.child_var = {
			'id': None
		}
		if var:
			self.child_var['id'] = var
	def update(self, new_var):
		self.child_var['id'] = new_var
	def get(self):
		return self.child_var

class parent(object):
	def __init__(self):
		self.child_records = {}
	def new(self, name, var):
		record = child(var)
		self.child_records[name] = record
	def get(self, name):
		return self.child_records.get(name)

p = parent()

p.new('A', 2)
p.new('B', 3)

print(p.get('A').get())
print(p.get('B').get())