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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Pythonic VS String Syntax
Import the LArray library
Step1:  The LArray library offers two syntaxes to build axes and make selections and aggregations.
The first one is more Pythonic (uses Python structures) 
For example, you can create an age_category axis as follows
Step2:  The second one consists of using strings that are parsed.
It is shorter to type. The same age_category axis could have been generated as follows
Step3:  <div class="alert alert-warning">
  **Warning
Step4:  The special syntax start..stop generates a sequence of labels
Step5:  When creating an array, it is possible to define several axes in the same string using ;
Step6:  Selection
Starting from the array
Step7:  an example of a selection using the Pythonic syntax is
Step8:  Using the String syntax, the same selection becomes
Step9:  Aggregation
An example of an aggregation using the Pythonic syntax is
Step10:  Using the String syntax, the same aggregation becomes
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Python Code:
from larray import *
Explanation: Pythonic VS String Syntax
Import the LArray library:
End of explanation
age_category = Axis(["0-9", "10-17", "18-66", "67+"], "age_category")
age_category
Explanation: The LArray library offers two syntaxes to build axes and make selections and aggregations.
The first one is more Pythonic (uses Python structures) 
For example, you can create an age_category axis as follows:
End of explanation
age_category = Axis("age_category=0-9,10-17,18-66,67+")
age_category
Explanation: The second one consists of using strings that are parsed.
It is shorter to type. The same age_category axis could have been generated as follows:
End of explanation
a = Axis('a=a0,a1,a2,a3')
a
Explanation: <div class="alert alert-warning">
  **Warning:** The drawback of the string syntax is that some characters such as `, ; = : .. [ ] >>`
have a special meaning and cannot be used with the ``String`` syntax. 
If you need to work with labels containing such special characters (when importing data from an external source for example), you have to use the ``Pythonic`` syntax which allows to use any character in labels.
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String Syntax
Axes And Arrays creation
The string syntax allows to easily create axes.
When creating one axis, the labels are separated using ,:
End of explanation
a = Axis('a=a0..a3')
a
Explanation: The special syntax start..stop generates a sequence of labels:
End of explanation
arr = zeros("a=a0..a2; b=b0,b1; c=c0..c5")
arr
Explanation: When creating an array, it is possible to define several axes in the same string using ;
End of explanation
immigration = load_example_data('demography_eurostat').immigration
immigration.info
Explanation: Selection
Starting from the array:
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# since the labels 'Belgium' and 'Netherlands' also exists in the 'citizenship' axis, 
# we need to explicitly specify that we want to make a selection over the 'country' axis
immigration_subset = immigration[X.country['Belgium', 'Netherlands'], 'Female', 2015:]
immigration_subset
Explanation: an example of a selection using the Pythonic syntax is:
End of explanation
immigration_subset = immigration['country[Belgium,Netherlands]', 'Female', 2015:]
immigration_subset
Explanation: Using the String syntax, the same selection becomes:
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immigration.mean((X.time[2014::2] >> 'even_years', X.time[::2] >> 'odd_years'), 'citizenship')
Explanation: Aggregation
An example of an aggregation using the Pythonic syntax is:
End of explanation
immigration.mean('time[2014::2] >> even_years; time[::2] >> odd_years', 'citizenship')
Explanation: Using the String syntax, the same aggregation becomes:
End of explanation
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