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README.md

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 # atdict
 
-Attribute-access ordered dictionary
+An attribute-access ordered dictionary in Python
+
+*****
+
+_atdict_ is an attribute-access ordered dictionary. You can use a key
+name as an attribute to access the value of the dictionary for a key,
+for example, `o.key_name` rather than `o['key_name']`. Only a minimum
+set of methods are implemented so as to minimize the chances of name
+conflicts.
+
+_atdict_ was originally developed as the class
+[`Object`](https://github.com/alphatwirl/scribblers/blob/v0.10.0/scribblers/obj.py)
+in [_scribblers_](https://github.com/alphatwirl/scribblers), which
+represents _event objects_ in
+[_alphatwirl_](https://github.com/alphatwirl/alphatwirl). Since
+`Object` became useful in other contexts, it was released as an
+independent package as _atdict_.
+
+*****
+
+- [**Requirement**](#requirement)
+- [**Install**](#install)
+- [**How to use**](#how-to-use)
+    - [Import atdict](#import-atdict)
+    - [Initialize atdict](#initialize-atdict)
+    - [Access to a value](#access-to-a-value)
+    - [Modify a value](#modify-a-value)
+    - [Add a key](#add-a-key)
+    - [Delete a key](#delete-a-key)
+    - [Copy and deepcopy](#copy-and-deepcopy)
+    - [Pickle](#pickle)
+- [**License**](#license)
+- [**Contact**](#contact)
+
+*****
+
+## Requirement
+
+- Python 2.7, 3.6, or 3.7
+
+*****
+
+## Install
+
+You can install with `pip`.
+
+```bash
+$ pip install -U atdict
+```
+
+*****
+
+## How to use
+
+### Import atdict
+
+Import `atdict` from the package `atdict`.
+
+```python
+from atdict import atdict
+```
+
+### Initialize atdict
+
+You can initialize an `atdict` with any arguments that can initialize
+[`collections.OrderedDict`](https://docs.python.org/3/library/collections.html#ordereddict-objects).
+
+For example:
+```python
+o1 = atdict([('foo', 40), ('bar', 'ham')])
+print(o1)
+```
+
+It will prints.
+
+```python
+atdict(foo=40, bar='ham')
+```
+
+An `atdict` can be also initialized with another `atdict`.
+
+```
+o2 = atdict(o1)
+print(o2)
+```
+
+The `o2` is initialized with a (shallow) copy of the contents of `o1`.
+
+```
+atdict(foo=40, bar='ham')
+```
+
+### Access to a value
+
+Yon can use a key name as an attribute of `atdict`.
+
+```python
+print(o1.foo)
+```
+
+This will print the value for the key `foo`, which is `40`.
+
+```
+40
+```
+
+### Modify a value
+
+To modify a value, you can assign a new value to the attribute.
+
+```python
+o1.foo = 50
+print(o1)
+```
+
+```
+atdict(foo=50, bar='ham')
+```
+
+The value for the key `foo` changed from `40` to `50`.
+
+### Add a key
+
+To add a key, you can also assign a value to the attribute
+
+```python
+o1.baz = 'eggs'
+print(o1)
+```
+
+```
+atdict(foo=50, bar='ham', baz='eggs')
+```
+
+### Delete a key
+
+`del` deletes a key.
+
+```python
+del o1.bar
+print(o1)
+```
+
+```
+atdict(foo=50, baz='eggs')
+```
+
+### Copy and deepcopy
+
+A copy will be created if `atdict` is initialized with another
+`atdict`. However, this will be a _shallow_ copy.
+
+```python
+l = [1, 2]
+o1 = atdict([('foo', l)])
+o2 = atdict(o1)
+print(o2.foo is o1.foo)
+```
+
+```
+True
+```
+
+To make a _deep_ copy, you can use `copy.deepcopy()`.
+
+```python
+import copy
+l = [1, 2]
+o1 = atdict([('foo', l)])
+o2 = copy.deepcopy(o1)
+print(o2)
+```
+
+```
+atdict(foo=[1, 2])
+```
+
+`o2.foo` and `o1.foo` are not the same object.
+
+```python
+print(o2.foo is o1.foo)
+```
+
+```
+False
+```
+
+### Pickle
+
+An `atdict` is picklable as long as all values are picklable.
+
+```python
+import pickle
+o1 = atdict([('foo', 40), ('bar', 'ham')])
+p1 = pickle.dumps(o1)
+o2 = pickle.loads(p1)
+print(o2)
+```
+
+```
+atdict(foo=40, bar='ham')
+```
+
 
 *****