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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get(identifier, value=None):
 """Getter for loading from strings; returns value if can't load."""

  if value is None:
    value = identifier
  if identifier is None:
    return None
  elif isinstance(identifier, dict):
    try:
      return deserialize(identifier)
    except ValueError:
      return value
  elif isinstance(identifier, six.string_types):
    config = {'class_name': str(identifier), 'config': {}}
    try:
      return deserialize(config)
    except ValueError:
      return value
  elif callable(identifier):
    return identifier
  return value