text: from __future__ import unicode_literals, division, print_function, absolute_import
  
  import argparse
  import io
  import sys
  
  import pkg_resources
  from sqlalchemy.engine import create_engine
  from sqlalchemy.schema import MetaData
  
  from sqlacodegen.codegen import CodeGenerator
  
  
  def main():
      parser = argparse.ArgumentParser(
          description='Generates SQLAlchemy model code from an existing database.')
      parser.add_argument('url', nargs='?', help='SQLAlchemy url to the database')
      parser.add_argument('--version', action='store_true', help="print the version number and exit")
      parser.add_argument('--schema', help='load tables from an alternate schema')
      parser.add_argument('--tables', help='tables to process (comma-separated, default: all)')
      parser.add_argument('--noviews', action='store_true', help="ignore views")
      parser.add_argument('--noindexes', action='store_true', help='ignore indexes')
      parser.add_argument('--noconstraints', action='store_true', help='ignore constraints')
      parser.add_argument('--nojoined', action='store_true',
                          help="don't autodetect joined table inheritance")
      parser.add_argument('--noinflect', action='store_true',
                          help="don't try to convert tables names to singular form")
      parser.add_argument('--noclasses', action='store_true',
                          help="don't generate classes, only tables")
      parser.add_argument('--nocomments', action='store_true', help="don't render column comments")
      parser.add_argument('--outfile', help='file to write output to (default: stdout)')
      parser.add_argument('--multifile', action='store_true',
                          help='export each model/table to a separate file')
      args = parser.parse_args()
  
      if args.version:
          version = pkg_resources.get_distribution('sqlacodegen').parsed_version
          print(version.public)
          return
      if not args.url:
          print('You must supply a url\n', file=sys.stderr)
          parser.print_help()
          return
  
      # Use reflection to fill in the metadata
      engine = create_engine(args.url)
      metadata = MetaData(engine)
      tables = args.tables.split(',') if args.tables else None
      metadata.reflect(engine, args.schema, not args.noviews, tables)
  
      # Write the generated model code to the specified file or standard output
      outfile = io.open(args.outfile, 'w', encoding='utf-8') if args.outfile else sys.stdout
      generator = CodeGenerator(metadata, args.noindexes, args.noconstraints, args.nojoined,
                                args.noinflect, args.noclasses, nocomments=args.nocomments)
      if args.multifile:
          generator.render_multifile()
      else:
          generator.render(outfile)
  