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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:
 Defining
namedtuple instances are just as memory efficient as regular tuples because they do not have per-instance dictionaries. Each kind of namedtuple is represented by its own class, which is created by using the namedtuple() factory function. The arguments are the name of the new class and a string containing the names of the elements.
Step1:  Just like a regular tuple, a namedtuple is immutable. This restriction allows tuple instances to have a consistent hash value, which makes it possible to use them as keys in dictionaries and to be included in sets.
Step2:  Invalid Field Names
Field names are invalid if they are repeated or conflict with Python keywords.
Step3:  In situations where a namedtuple is created based on values outside the control of the program (such as to represent the rows returned by a database query, where the schema is not known in advance), the rename option should be set to True so the invalid fields are renamed.
Step4:  Special Attributes
namedtuple provides several useful attributes and methods for working with subclasses and instances. All of these built-in properties have names prefixed with an underscore (_), which by convention in most Python programs indicates a private attribute. For namedtuple, however, the prefix is intended to protect the name from collision with user-provided attribute names.
The names of the fields passed to namedtuple to define the new class are saved in the _fields attribute.
Step5:  namedtuple instances can be converted to OrderedDict instances using _asdict().
Step6:  The _replace() method builds a new instance, replacing the values of some fields in the process.
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Python Code:
import collections
Person = collections.namedtuple('Person', 'name age')
bob = Person(name='Bob', age=30)
print('\nRepresentation:', bob)
jane = Person(name='Jane', age=29)
print('\nField by name:', jane.name)
print('\nFields by index:')
for p in [bob, jane]:
    print('{} is {} years old'.format(*p))
Explanation: Defining
namedtuple instances are just as memory efficient as regular tuples because they do not have per-instance dictionaries. Each kind of namedtuple is represented by its own class, which is created by using the namedtuple() factory function. The arguments are the name of the new class and a string containing the names of the elements.
End of explanation
import collections
Person = collections.namedtuple('Person', 'name age')
pat = Person(name='Pat', age=12)
print('\nRepresentation:', pat)
pat.age = 21
Explanation: Just like a regular tuple, a namedtuple is immutable. This restriction allows tuple instances to have a consistent hash value, which makes it possible to use them as keys in dictionaries and to be included in sets.
End of explanation
import collections
try:
    collections.namedtuple('Person', 'name class age')
except ValueError as err:
    print(err)
try:
    collections.namedtuple('Person', 'name age age')
except ValueError as err:
    print(err)
Explanation: Invalid Field Names
Field names are invalid if they are repeated or conflict with Python keywords.
End of explanation
import collections
with_class = collections.namedtuple(
    'Person', 'name class age',
    rename=True)
print(with_class._fields)
two_ages = collections.namedtuple(
    'Person', 'name age age',
    rename=True)
print(two_ages._fields)
Explanation: In situations where a namedtuple is created based on values outside the control of the program (such as to represent the rows returned by a database query, where the schema is not known in advance), the rename option should be set to True so the invalid fields are renamed.
End of explanation
import collections
Person = collections.namedtuple('Person', 'name age')
bob = Person(name='Bob', age=30)
print('Representation:', bob)
print('Fields:', bob._fields)
Explanation: Special Attributes
namedtuple provides several useful attributes and methods for working with subclasses and instances. All of these built-in properties have names prefixed with an underscore (_), which by convention in most Python programs indicates a private attribute. For namedtuple, however, the prefix is intended to protect the name from collision with user-provided attribute names.
The names of the fields passed to namedtuple to define the new class are saved in the _fields attribute.
End of explanation
import collections
Person = collections.namedtuple('Person', 'name age')
bob = Person(name='Bob', age=30)
print('Representation:', bob)
print('As Dictionary:', bob._asdict())
Explanation: namedtuple instances can be converted to OrderedDict instances using _asdict().
End of explanation
import collections
Person = collections.namedtuple('Person', 'name age')
bob = Person(name='Bob', age=30)
print('\nBefore:', bob)
bob2 = bob._replace(name='Robert')
print('After:', bob2)
print('Same?:', bob is bob2)
Explanation: The _replace() method builds a new instance, replacing the values of some fields in the process.
End of explanation
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