"""Backport of importlib.import_module from 3.x."""
import sys

def _resolve_name(name, package, level):
    """Return the absolute name of the module to be imported."""
    level -= 1
    try:
        if package.count('.') < level:
            raise ValueError("attempted relative import beyond top-level "
                              "package")
    except AttributeError:
        raise ValueError("__package__ not set to a string")
    base = package.rsplit('.', level)[0]
    if name:
        return "%s.%s" % (base, name)
    else:
        return base


def import_module(name, package=None):
    """Import a module.

    The 'package' argument is required when performing a relative import. It
    specifies the package to use as the anchor point from which to resolve the
    relative import to an absolute import.

    """
    if name.startswith('.'):
        if not package:
            raise TypeError("relative imports require the 'package' argument")
        level = 0
        for character in name:
            if character != '.':
                break
            level += 1
        name = _resolve_name(name[level:], package, level)
    __import__(name)
    return sys.modules[name]

"""Backport of importlib.import_module from 3.x."""
# While not critical (and in no way guaranteed!), it would be nice to keep this
# code compatible with Python 2.3.
import sys

def _resolve_name(name, package, level):
    """Return the absolute name of the module to be imported."""
    level -= 1
    try:
        if package.count('.') < level:
            raise ValueError("attempted relative import beyond top-level "
                              "package")
    except AttributeError:
        raise ValueError("'package' not set to a string")
    try:
        # rpartition is more "correct" and rfind is just as easy to use, but
        # neither are in Python 2.3.
        dot_rindex = package.rindex('.', level)[0]
        base = package[:dot_rindex]
    except ValueError:
        base = package
    if name:
        return "%s.%s" % (base, name)
    else:
        return base


def import_module(name, package=None):
    """Import a module.

    The 'package' argument is required when performing a relative import. It
    specifies the package to use as the anchor point from which to resolve the
    relative import to an absolute import.

    """
    if name.startswith('.'):
        if not package:
            raise TypeError("relative imports require the 'package' argument")
        level = 0
        for character in name:
            if character != '.':
                break
            level += 1
        name = _resolve_name(name[level:], package, level)
    # Try to import specifying the level to be as accurate as possible, but
    # realize that keyword arguments are not found in Python 2.3.
    try:
        __import__(name, level=0)
    except TypeError:
        __import__(name)
    return sys.modules[name]

Make importlib backwards-compatible to Python 2.2 (but this is not promised to last; just doing it to be nice).
Make importlib backwards-compatible to Python 2.2 (but this is not promised to
last; just doing it to be nice).

Also fix a message for an exception.

  """Backport of importlib.import_module from 3.x."""
+ # While not critical (and in no way guaranteed!), it would be nice to keep this
+ # code compatible with Python 2.3.
  import sys
  
  def _resolve_name(name, package, level):
      """Return the absolute name of the module to be imported."""
      level -= 1
      try:
          if package.count('.') < level:
              raise ValueError("attempted relative import beyond top-level "
                                "package")
      except AttributeError:
-         raise ValueError("__package__ not set to a string")
+         raise ValueError("'package' not set to a string")
-     base = package.rsplit('.', level)[0]
+     try:
+         # rpartition is more "correct" and rfind is just as easy to use, but
+         # neither are in Python 2.3.
+         dot_rindex = package.rindex('.', level)[0]
+         base = package[:dot_rindex]
+     except ValueError:
+         base = package
      if name:
          return "%s.%s" % (base, name)
      else:
          return base
  
  
  def import_module(name, package=None):
      """Import a module.
  
      The 'package' argument is required when performing a relative import. It
      specifies the package to use as the anchor point from which to resolve the
      relative import to an absolute import.
  
      """
      if name.startswith('.'):
          if not package:
              raise TypeError("relative imports require the 'package' argument")
          level = 0
          for character in name:
              if character != '.':
                  break
              level += 1
          name = _resolve_name(name[level:], package, level)
+     # Try to import specifying the level to be as accurate as possible, but
+     # realize that keyword arguments are not found in Python 2.3.
+     try:
+         __import__(name, level=0)
+     except TypeError:
-     __import__(name)
+         __import__(name)
      return sys.modules[name]
  
Make importlib backwards-compatible to Python 2.2 (but this is not promised to last; just doing it to be nice).
## Code Before:
"""Backport of importlib.import_module from 3.x."""
import sys

def _resolve_name(name, package, level):
    """Return the absolute name of the module to be imported."""
    level -= 1
    try:
        if package.count('.') < level:
            raise ValueError("attempted relative import beyond top-level "
                              "package")
    except AttributeError:
        raise ValueError("__package__ not set to a string")
    base = package.rsplit('.', level)[0]
    if name:
        return "%s.%s" % (base, name)
    else:
        return base


def import_module(name, package=None):
    """Import a module.

    The 'package' argument is required when performing a relative import. It
    specifies the package to use as the anchor point from which to resolve the
    relative import to an absolute import.

    """
    if name.startswith('.'):
        if not package:
            raise TypeError("relative imports require the 'package' argument")
        level = 0
        for character in name:
            if character != '.':
                break
            level += 1
        name = _resolve_name(name[level:], package, level)
    __import__(name)
    return sys.modules[name]

## Instruction:
Make importlib backwards-compatible to Python 2.2 (but this is not promised to last; just doing it to be nice).
## Code After:
"""Backport of importlib.import_module from 3.x."""
# While not critical (and in no way guaranteed!), it would be nice to keep this
# code compatible with Python 2.3.
import sys

def _resolve_name(name, package, level):
    """Return the absolute name of the module to be imported."""
    level -= 1
    try:
        if package.count('.') < level:
            raise ValueError("attempted relative import beyond top-level "
                              "package")
    except AttributeError:
        raise ValueError("'package' not set to a string")
    try:
        # rpartition is more "correct" and rfind is just as easy to use, but
        # neither are in Python 2.3.
        dot_rindex = package.rindex('.', level)[0]
        base = package[:dot_rindex]
    except ValueError:
        base = package
    if name:
        return "%s.%s" % (base, name)
    else:
        return base


def import_module(name, package=None):
    """Import a module.

    The 'package' argument is required when performing a relative import. It
    specifies the package to use as the anchor point from which to resolve the
    relative import to an absolute import.

    """
    if name.startswith('.'):
        if not package:
            raise TypeError("relative imports require the 'package' argument")
        level = 0
        for character in name:
            if character != '.':
                break
            level += 1
        name = _resolve_name(name[level:], package, level)
    # Try to import specifying the level to be as accurate as possible, but
    # realize that keyword arguments are not found in Python 2.3.
    try:
        __import__(name, level=0)
    except TypeError:
        __import__(name)
    return sys.modules[name]
