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The process for creating a table through the use of the "create as select" statement using sqlalchemy is as follows:

1. Import the necessary modules: sqlalchemy, create_engine, MetaData, Table, Column, and select.

2. Define the database connection using the create_engine() function.

3. Create a metadata object using the MetaData() function.

4. Define the columns that the new table will have, using the Column() function.

5. Create the table object using the Table() function, passing in the metadata object created earlier and the name of the new table.

6. Use the select() function to define the SQL query for selecting the data that will be used to create the new table.

7. Use the "create as select" statement to create the new table with the data selected by the SQL query. The "create as select" statement is used in conjunction with the execute() function of the database connection object.

8. Commit the transaction using the commit() function of the database connection object.

Here is an example code snippet that demonstrates the above process:

from sqlalchemy import create_engine, MetaData, Table, Column, select

# Define the database connection
engine = create_engine('postgresql://username:password@host:port/database')

# Create a metadata object
metadata = MetaData()

# Define the columns for the new table
id_col = Column('id', Integer, primary_key=True)
name_col = Column('name', String)
age_col = Column('age', Integer)

# Create the table object
new_table = Table('new_table', metadata, id_col, name_col, age_col)

# Define the select query to get data to populate the new table
select_query = select([old_table.c.id, old_table.c.name, old_table.c.age])

# Create the new table as a select query
engine.execute(new_table.insert().from_select(['id', 'name', 'age'], select_query))

# Commit the transaction
engine.commit()