human
Solve the following python programming problem given the following code:
@ classmethod 
def ReadStaticVirtualMachineFile(cls, file_obj) : 
    'Read a file describing the static VMs to use.

    This function will read the static VM information from the provided file,
    instantiate VMs corresponding to the info, and add the VMs to the static
    VM pool. The provided file should contain a single array in JSON-format.
    Each element in the array must be an object with required format:

      ip_address: string.
      user_name: string.
      keyfile_path: string.
      ssh_port: integer, optional. Default 22
      internal_ip: string, optional.
      zone: string, optional.
      local_disks: array of strings, optional.
      scratch_disk_mountpoints: array of strings, optional
      os_type: string, optional (see package_managers)
      install_packages: bool, optional

    Args:
      file_obj: An open handle to a file containing the static VM info.

    Raises:
      ValueError: On missing required keys, or invalid keys.
    ' 
    vm_arr = json.load (file_obj) 
    if (not isinstance (vm_arr, list)) : 
        raise ValueError (('Invalid static VM file. Expected array, got: %s.' % type (vm_arr))) 
required_keys = frozenset (['ip_address', 'user_name']) 
    linux_required_keys = (required_keys | frozenset (['keyfile_path'])) 
    required_keys_by_os = { 
        os_types.WINDOWS : (required_keys | frozenset (['password'])), 
        os_types.DEBIAN : linux_required_keys, 
        os_types.RHEL : linux_required_keys, 
        os_types.UBUNTU_CONTAINER : local_disks, 
} 
    required_keys = required_keys_by_os [FLAGS.os_type] 
    optional_keys = frozenset (['internal_ip', 'zone', 'local_disks', 'scratch_disk_mountpoints', 'os_type', 'ssh_port', 'install_packages']) 
    allowed_keys = (required_keys | optional_keys) 
    def VerifyItemFormat(item) : 
        'Verify that the decoded JSON object matches the required schema.' 
        item_keys = frozenset (item) 
        extra_keys = sorted ((item_keys - allowed_keys)) 
        missing_keys = (required_keys - item_keys) 
   ...

    
    

    Fix the buggy line: os_types.UBUNTU_CONTAINER : local_disks ,
assistant
#Here is Python code to fix the buggy line: os_types.

os_types.UBUNTU_CONTAINER : linux_required_keys ,