old_contents: import time
  
  
  # for dict
  def merge_dict(base_dict, *dicts):
      for dic in dicts:
          base_dict.update(dic) or base_dict
      return base_dict
  
  
  def datetime2timestamp(datetime):
      return int(time.mktime(datetime.timetuple()))
  
  
  def int_epoch_time(t=None):
      if not t:
          return int(time.time())
      return int(t)
  
  
  def is_float(string):
      try:
          float(string)
          return True
      except ValueError:
          return False
  
new_contents: import time
  import random
  
  
  # for dict
  def merge_dict(base_dict, *dicts):
      for dic in dicts:
          base_dict.update(dic) or base_dict
      return base_dict
  
  
  def datetime2timestamp(datetime):
      return int(time.mktime(datetime.timetuple()))
  
  
  def int_epoch_time(t=None):
      if not t:
          return int(time.time())
      return int(t)
  
  
  def is_float(string):
      try:
          float(string)
          return True
      except ValueError:
          return False
  
  
  def random_sleep(from_, to_):
      sleeping_time = random.uniform(from_, to_)
      time.sleep(sleeping_time)
  
subject: Add random sleep