def extract_error(self, errors, row_buffer, step_schema):
for error in errors:
if isinstance(
error,
tuple) and errors[0][1].__class__.__name__ == 'Invalid':
error_doc = error[1].message
error_doc = translate(_(error_doc), context=self.request)
field_title = 'Invalid'
field_name = 'Invalid'
elif isinstance(
error,
tuple) and errors[0][1].__class__.__name__ != 'Invalid':
error_doc = error[1].doc()
error_doc = translate(_(error_doc), context=self.request)
field_title = step_schema[error[0]].title
field_title = translate(_(field_title), context=self.request)
field_name = error[1].args[0]
else:
error_doc = error.doc()
error_doc = translate(_(error_doc), context=self.request)
field_title = ''
field_name = error.args[0]
error_message = ''
if not isinstance(field_name, list):
error_message = translate(_(field_name), context=self.request)
msg = u'{0}: {1} {2}; '.format(error_doc, field_title,
error_message)
row_buffer[0] = logging.ERROR
row_buffer[2] += msg
if isinstance(field_name, list):
self.extract_error(field_name, row_buffer, step_schema)
def __call__(self, context):
steps_vocabulary = SimpleVocabulary(
[SimpleTerm(value=u'step2', title=_(u'NA Extraction')),
SimpleTerm(value=u'step3', title=_(u'Library Construction')),
SimpleTerm(value=u'step4', title=_(u'Computer Detecting'))]
)
return steps_vocabulary
def fetch_data(self, field_obj, field_value, _obj, row_buffer):
field_type = field_obj[1].__class__.__name__
field_title = field_obj[1].title
field_name = field_obj[0]
if field_type in ('NamedBlobImage', 'NamedBlobFile'):
request = urllib2.Request(url=field_value)
try:
response = urllib2.urlopen(request)
filename = os.path.basename(response.url)
if field_type == 'NamedBlobFile':
blob_file = NamedBlobFile(data=response.read(),
filename=safe_unicode(filename))
elif field_type == 'NamedBlobImage':
blob_file = NamedBlobImage(data=response.read(),
filename=safe_unicode(filename))
setattr(_obj, field_name, blob_file)
return True
except Exception:
field_title = translate(_(field_title), context=self.request)
error_doc = translate(
_("""The URL you have provided could not be reached."""),
context=self.request)
msg = u'{0}: {1}; '.format(error_doc, field_title)
row_buffer[2] += msg
return False
def progress_steps(context):
steps_vocabulary = SimpleVocabulary(
[SimpleTerm(value=u'step1', title=_(u'Blood Sample')),
SimpleTerm(value=u'step2', title=_(u'NA Extraction')),
SimpleTerm(value=u'step3', title=_(u'Library Construction')),
SimpleTerm(value=u'step4', title=_(u'Computer Detecting')),
SimpleTerm(value=u'step5', title=_(u'Analysis Results'))]
)
return steps_vocabulary
def dumpOutput(self, data):
"""
"""
batch_list = data.get('batch_list', [])
add_count = 0
for entry in batch_list:
uuid = entry['uuid']
obj = api.content.uuidToObject(uuid)
change_note = entry['changeNote']
valid_steps = (u'step2', u'step3', u'step4')
steps = entry['steps']
try:
index = valid_steps.index(steps)
except ValueError:
index = 0
start, end = 0, utils.steps_start_end[index][1]
step_field = utils.fields_name()[start:end]
step_field.extend(['gid', 'creation_date', 'title'])
if obj:
container = obj.aq_parent
new_obj = createContentInContainer(container,
portal_type='Tumour')
[
setattr(new_obj, name, getattr(obj, name, ''))
for name in step_field
]
[setattr(new_obj, k, v) for k, v in entry.items()]
new_obj.steps = utils.progress_steps[index]
add_count += 1
change_note = u"{0} - {1}: {2}.".format(
translate(self.label, context=api.portal.getRequest()),
translate(_(steps), context=api.portal.getRequest()),
change_note if change_note else '')
annotation = IAnnotations(self.context.REQUEST)
annotation['plone.app.versioningbehavior' +
'-changeNote'] = change_note
modified(new_obj)
if add_count:
api.portal.show_message(
_(u'${count} Item created', mapping={'count': add_count}),
self.request, 'info')
logger.info(
'{count} item(s) added successfully.'.format(count=add_count))
return add_count
def dumpOutput(self, data):
batch_list = data.get('batch_list', [])
add_count = 0
generator = getUtility(IUUIDGenerator)
gid = generator()
today = datetime.datetime.today()
year, month, day = today.year, today.month, today.day
container = make_folder(self.aq_parent, (year, month, day))
for entry in batch_list:
obj = createContentInContainer(container,
portal_type='Tumour',
gid=gid)
if obj:
add_count += 1
fields = dict((field[0], field[1])
for field in getFieldsInOrder(self._list_schema))
for name, value in entry.items():
if name in fields and fields[name].readonly is False:
setattr(obj, name, value)
obj.steps = 'step1'
if 'sample_no' in entry:
obj.title = entry['sample_no']
modified(obj)
api.portal.show_message(
_(u'${count} Item created', mapping={'count': add_count}),
self.request, 'info')
logger.info(
'{count} item(s) added successfully.'.format(count=add_count))
return add_count
def dumpOutput(self, data):
"""
"""
batch_list = data.get('batch_list', [])
edit_count = 0
for entry in batch_list:
uuid = entry['uuid']
obj = api.content.uuidToObject(uuid)
if obj:
transition = entry['transition_state']
change_note = entry['changeNote']
if transition:
api.content.transition(obj=obj,
transition=transition,
comment=change_note)
edit_count += 1
obj.reindexObject(idxs=['review_state'])
if edit_count:
api.portal.show_message(
_(u'${count} Item state changed',
mapping={'count': edit_count}), self.request, 'info')
logger.info(
'{count} item(s) state changed.'.format(count=edit_count))
return edit_count
def validate_url(value):
if value != '' and not url_exists(value):
raise InvalidURL(
_(u"The URL you have provided could not be reached. "
u"Please verify the URL is correct "
u"and that the network location is reachable.")
)
return True
class ILibraryConstruction(model.Schema):
uuid = schema.TextLine(
title=_(u"UUID"),
required=True,
readonly=False,
)
sample_no = schema.TextLine(
title=_(u"Sample number"),
required=False,
readonly=False,
)
library_time = schema.Datetime(
title=_(u"Library construction time"),
constraint=validate_time,
required=True,
)
library_barcode = schema.TextLine(
title=_(u"Library barcode"),
required=False,
)
library_concentration = schema.Float(
title=_(u"Library concentration (NG/UL)"),
min=0.0,
required=False,
)
library_operator = schema.TextLine(
title=_(u"Library construction operator"),
required=False,
)
library_kit_no = schema.TextLine(
title=_(u"Library kit lot number"),
required=False,
)
library_location = schema.TextLine(
title=_(u"Library location"),
required=False,
)
capture_concentration = schema.Float(
title=_(u"Post capture concentration (NG/UL)"),
min=0.0,
required=False,
)
class AnalysisResultsEditForm(NAExtractionEditForm):
""""""
_add_permission = 'gene.tumour: Add AnalysisResults'
_list_schema = IAnalysisResultsEdit
label = _(u'Analysis Results')
prefix = 'form.tumour.results'
fields = field.Fields(IAnalysisResultsList)
fields['batch_list'].widgetFactory = DataGridFieldFactory
class ComputerDetectingEditForm(NAExtractionEditForm):
""""""
_add_permission = 'gene.tumour: Add ComputerDetecting'
_list_schema = IComputerDetecting
label = _(u'Computer Detecting')
prefix = 'form.tumour.detecting'
fields = field.Fields(IComputerDetectingList)
fields['batch_list'].widgetFactory = DataGridFieldFactory
class LibraryConstructionEditForm(NAExtractionEditForm):
""""""
_add_permission = 'gene.tumour: Add LibraryConstruction'
_list_schema = ILibraryConstruction
label = _(u'Library Construction')
prefix = 'form.tumour.library'
fields = field.Fields(ILibraryConstructionList)
fields['batch_list'].widgetFactory = DataGridFieldFactory
class IAnalysisResultsEdit(model.Schema):
uuid = schema.TextLine(
title=_(u"UUID"),
required=True,
readonly=False,
)
sample_no = schema.TextLine(
title=_(u"Sample number"),
required=False,
readonly=False,
)
result = schema.Choice(
title=_(u"Result"),
required=False,
vocabulary=u"gene.tumour.vocabulary.analysis_result",
)
result_info = schema.TextLine(
title=_(u"Result information"),
required=False,
)
quality_file = field.NamedBlobFile(
title=_(u"Quality control document"),
required=False,
)
result_file = field.NamedBlobFile(
title=_(u"Result detail"),
required=False,
)
class ChangeNoteForm(AutoExtensibleForm, form.EditForm):
schema = IVersionable
name = 'ChangeNoteForm'
label = _(u"Add change notes")
description = _(u"Add change notes, note the notes cannot be changed.")
def update(self):
self.request.set('disable_border', True)
super(ChangeNoteForm, self).update()
@button.buttonAndHandler(_(u'Save'))
def handleApply(self, action):
data, errors = self.extractData()
if errors:
self.status = self.formErrorsMessage
return
changes = {}
if 'changeNote' in data and data['changeNote'] is not None and \
len(data) == 1:
obj = self.getContent()
obj.description += data['changeNote'] + u'\n'
changes = self.applyChanges(data)
if changes:
api.portal.show_message(
_(u"Note has been added."), self.request, 'info')
else:
api.portal.show_message(
_(u"Note has not been added."), self.request, 'warn')
self.status = 'form status'
contextURL = self.context.absolute_url()
self.request.response.redirect(contextURL)
@button.buttonAndHandler(_(u"Cancel"))
def handleCancel(self, action):
contextURL = self.context.absolute_url()
self.request.response.redirect(contextURL)
def handleApply(self, action):
data, errors = self.extractData()
if errors:
self.status = self.formErrorsMessage
return
changes = {}
if 'changeNote' in data and data['changeNote'] is not None and \
len(data) == 1:
obj = self.getContent()
obj.description += data['changeNote'] + u'\n'
changes = self.applyChanges(data)
if changes:
api.portal.show_message(
_(u"Note has been added."), self.request, 'info')
else:
api.portal.show_message(
_(u"Note has not been added."), self.request, 'warn')
self.status = 'form status'
contextURL = self.context.absolute_url()
self.request.response.redirect(contextURL)
def dumpOutput(self, data):
batch_list = data.get('batch_list', [])
add_count = 0
edit_count = 0
for entry in batch_list:
uuid = entry['uuid']
obj = api.content.uuidToObject(uuid)
if obj:
edit_count += 1
fields = dict((field[0], field[1])
for field in getFieldsInOrder(self._list_schema))
for name, value in entry.items():
if name in fields and fields[name].readonly is False:
setattr(obj, name, value)
if 'sample_no' in entry:
obj.title = entry['sample_no']
if self.new_steps and self.new_steps != u'step*':
old_steps = obj.steps
obj.steps = self.new_steps
notify(StepsChangedEvent(obj, old_steps, self.new_steps))
modified(obj)
if add_count:
api.portal.show_message(
_(u'${count} Item created', mapping={'count': add_count}),
self.request, 'info')
logger.info(
'{count} item(s) added successfully.'.format(count=add_count))
if edit_count:
api.portal.show_message(
_(u'${count} Item edited', mapping={'count': edit_count}),
self.request, 'info')
logger.info(
'{count} items edited successfully.'.format(count=edit_count))
return add_count or edit_count
def __init__(self, context, request):
super(ImportExcel, self).__init__(context, request)
self.context = context
self.request = request
add_bundle_on_request(self.request, 'gene-tumour-main')
self.request['disable_border'] = True
for trans, invert in [
(invert_situation_local, invert_situation_dict),
(invert_na_types_local, invert_na_types_dict),
(invert_result_local, invert_result_dict),
]:
if not trans:
for key in invert:
trans[translate(_(key), context=request)] = invert[key]
def pre_older_after(obj):
prev = 'sampling_time'
after = 'received_time'
prev_value = getattr(obj, prev, None)
after_value = getattr(obj, after, None)
if after_value is not None:
if (prev_value is not None
and isinstance(prev_value, datetime.datetime)
and isinstance(after_value, datetime.datetime)
and prev_value > after_value):
raise Invalid(
_(u'After steps time must be greater than '
u'or equal to the previous steps time'))
def getContent(self):
data = {'batch_list': []}
names = getFieldNamesInOrder(self._list_schema)
for obj in self.items:
record = {}
for name in names:
record[name] = getattr(obj, name, None)
record['uuid'] = obj.UID()
record['review_state'] = translate(_(
api.content.get_state(obj).title()),
context=api.portal.getRequest())
data['batch_list'].append(record)
return data
def __call__(self, context):
if isinstance(context, dict) and 'uuid' in context:
obj = api.content.uuidToObject(context['uuid'])
workflow = api.portal.get_tool('portal_workflow')
actions = workflow.listActions(object=obj)
states_vocabulary = SimpleVocabulary(
[SimpleTerm(value=action['id'],
title=translate(_(action['name']),
context=api.portal.getRequest()))
for action in actions]
)
else:
states_vocabulary = SimpleVocabulary([])
return states_vocabulary
def dumpOutput(self, data):
"""
"""
batch_list = data.get('batch_list', [])
edit_count = 0
for entry in batch_list:
uuid = entry['uuid']
obj = api.content.uuidToObject(uuid)
change_note = entry['changeNote']
if obj:
old_steps = obj.steps
if old_steps != entry['steps']:
obj.steps = entry['steps']
edit_count += 1
notify(StepsChangedEvent(obj, old_steps, entry['steps']))
change_note = u"{0} - {1}->{2}: {3}.".format(
translate(self.label, context=api.portal.getRequest()),
translate(_(old_steps),
context=api.portal.getRequest()),
translate(_(obj.steps),
context=api.portal.getRequest()),
change_note if change_note else '')
annotation = IAnnotations(self.context.REQUEST)
annotation['plone.app.versioningbehavior' +
'-changeNote'] = change_note
modified(obj)
if edit_count:
api.portal.show_message(
_(u'${count} Item edited', mapping={'count': edit_count}),
self.request, 'info')
logger.info('{count} item(s) edited successfully.'.format(
count=edit_count))
return edit_count
class WorkflowStateTransitionForm(ChangeStepsEditForm):
""""""
_add_permission = 'Review portal content'
_edit_permission = 'Review portal content'
_finishedAdd = False
_list_schema = IWorkflowStateTransition
label = _(u'Workflow state transition')
prefix = 'form.tumour.state'
fields = field.Fields(IWorkflowStateTransitionList)
fields['batch_list'].widgetFactory = DataGridFieldFactory
fields_readonly = [
'sample_no', 'barcode', 'name', 'steps', 'review_state', 'result',
'result_info'
]
def datagridInitialise(self, subform, widget):
pass
def dumpOutput(self, data):
"""
"""
batch_list = data.get('batch_list', [])
edit_count = 0
for entry in batch_list:
uuid = entry['uuid']
obj = api.content.uuidToObject(uuid)
if obj:
transition = entry['transition_state']
change_note = entry['changeNote']
if transition:
api.content.transition(obj=obj,
transition=transition,
comment=change_note)
edit_count += 1
obj.reindexObject(idxs=['review_state'])
if edit_count:
api.portal.show_message(
_(u'${count} Item state changed',
mapping={'count': edit_count}), self.request, 'info')
logger.info(
'{count} item(s) state changed.'.format(count=edit_count))
return edit_count
class IChangeSteps(model.Schema):
uuid = schema.TextLine(
title=_(u"UUID"),
required=True,
readonly=False,
)
sample_no = schema.TextLine(
title=_(u"Sample number"),
required=False,
readonly=False,
)
barcode = schema.TextLine(
title=_(u"Barcode"),
required=False,
readonly=False,
)
name = schema.TextLine(
title=_(u"Name"),
required=False,
readonly=False,
)
review_state = schema.TextLine(
title=_(u"Review state"),
required=False,
readonly=False,
)
steps = schema.Choice(
title=_(u"Steps"),
required=True,
vocabulary=u"gene.tumour.vocabulary.progress_steps"
)
changeNote = schema.TextLine(
title=_(u'label_change_note', default=u'Change Note'),
description=_(u'help_change_note',
default=u'Enter a comment that describes the changes '
u'you made.'),
required=False)
def fields_name_title(self):
split_point = 3
step5_start, step5_end = utils.steps_start_end[4]
fields_name = utils.fields_name()[-1:]
fields_name += ['review_state']
fields_name += utils.fields_name()[:split_point]
fields_name += utils.fields_name()[step5_start:step5_end]
fields_name += utils.fields_name()[split_point:step5_start]
fields_title = utils.fields_title()[-1:]
fields_title += [translate(_('Review state'), context=self.request)]
fields_title += utils.fields_title()[:split_point]
fields_title += utils.fields_title()[step5_start:step5_end]
fields_title += utils.fields_title()[split_point:step5_start]
return zip(fields_name, fields_title)
class NAExtractionEditForm(BloodSampleEditForm):
""""""
_add_permission = 'gene.tumour: Add NAExtraction'
_list_schema = INAExtraction
label = _(u'NA Extraction')
prefix = 'form.tumour.na'
fields = field.Fields(INAExtractionList)
fields['batch_list'].widgetFactory = DataGridFieldFactory
fields_readonly = [
'sample_no',
]
def updateWidgets(self, prefix=None):
super(NAExtractionEditForm, self).updateWidgets()
self.widgets['batch_list'].allow_insert = False
self.widgets['batch_list'].allow_delete = False
self.widgets['batch_list'].auto_append = False
def steps_date_valid(obj):
steps_date = [('sampling_time', 'received_time'),
('separation_time', 'extraction_time'),
('library_time',),
('template_time', 'sequencing_time')]
steps_date.reverse()
for index, names in enumerate(steps_date):
prev_date = []
[prev_date.extend(item) for item in steps_date[index + 1:]]
for after in names:
after_value = getattr(obj, after, None)
if after_value is not None:
for prev in prev_date:
prev_value = getattr(obj, prev, None)
if (prev_value is not None
and isinstance(prev_value, datetime.date)
and isinstance(after_value, datetime.date)
and prev_value > after_value):
raise Invalid(
_(u'After steps time must be greater than '
u'or equal to the previous steps time'))
class IComputerDetecting(model.Schema):
uuid = schema.TextLine(
title=_(u"UUID"),
required=True,
readonly=False,
)
sample_no = schema.TextLine(
title=_(u"Sample number"),
required=False,
readonly=False,
)
template_time = schema.Datetime(
title=_(u"Template preparation time"),
constraint=validate_time,
required=True,
)
template_operator = schema.TextLine(
title=_(u"Template preparation operator"),
required=False,
)
template_kit_no = schema.TextLine(
title=_(u"Template kit lot number"),
required=False,
)
ot_instrument_no = schema.TextLine(
title=_(u"OT instrument number"),
required=False,
)
es_instrument_no = schema.TextLine(
title=_(u"ES instrument number"),
required=False,
)
sequencing_time = schema.Datetime(
title=_(u"Sequencing time"),
constraint=validate_time,
required=True,
)
sequencing_operator = schema.TextLine(
title=_(u"Sequencing operator"),
required=False,
)
sequencing_server = schema.TextLine(
title=_(u"Sequencer number"),
required=False,
)
sequencing_ip = schema.TextLine(
title=_(u"Sequencing IP"),
required=False,
)
sequencing_filename = schema.TextLine(
title=_(u"Sequencing filename"),
required=False,
)
class INAExtraction(model.Schema):
uuid = schema.TextLine(
title=_(u"UUID"),
required=True,
readonly=False,
)
sample_no = schema.TextLine(
title=_(u"Sample number"),
required=False,
readonly=False,
)
task_no = schema.TextLine(
title=_(u"Task no"),
required=False,
)
separation_time = schema.Datetime(
title=_(u"Separation time"),
constraint=validate_time,
required=False,
)
separation_operator = schema.TextLine(
title=_(u"Separation operator"),
required=False,
)
plasma_location = schema.TextLine(
title=_(u"Plasma location"),
required=False,
)
separation_note = schema.TextLine(
title=_(u"Plasma separation note"),
required=False,
)
extraction_time = schema.Datetime(
title=_(u"Extraction time"),
constraint=validate_time,
required=True,
)
na_extraction_type = schema.List(
title=_(u"NA Extraction Type"),
required=True,
value_type=schema.Choice(
title=_(u"NA type"),
vocabulary="gene.tumour.vocabulary.na_types",
required=True),
)
na_plasma_volume = schema.Float(
title=_(u"NA plasma volume(ml)"),
min=0.0,
required=False,
)
na_concentration = schema.Float(
title=_(u"NA concentration (NG/UL)"),
min=0.0,
required=False,
)
absorbance = schema.Float(
title=_(u"Absorbance 260/280"),
min=0.0,
required=False,
)
na_kit_no = schema.TextLine(
title=_(u"NA extraction kit lot number"),
required=False,
)
na_operator = schema.TextLine(
title=_(u"NA extracting operator"),
required=False,
)
class IGeneTumourSettings(Interface):
sms_notify_enabled = schema.Bool(
title=_(u"SMS notification"),
description=_(u"If selected, the sent SMS notification to user."),
default=False
)
sms_notify_message = schema.Text(
title=_(u"SMS text"),
description=_(u"You need to send the text."),
default=u'',
required=False,
)
email_notify_enabled = schema.Bool(
title=_(u"Email notification"),
description=_(u"If selected, "
u"enabled step change Email message notifications."),
default=False
)
record_expire_days = schema.Int(
title=_(u"Record Expiration days"),
description=_(u"Please fill out an integer range: 1-365"),
min=0,
max=365,
default=0,
required=False)
record_expire_notify = schema.Choice(
title=_(u"Record expiration notification user group"),
description=_(u"When the entry has expired, "
u"send an email message to inform the user"),
vocabulary="plone.app.vocabularies.Groups",
required=False)
user_search_filter = schema.Dict(
title=_(u"User search filter"),
description=_(u"User search filter additional conditions"),
required=False,
key_type=schema.Choice(
title=_(u"User group"),
vocabulary="plone.app.vocabularies.Groups",
required=True),
value_type=schema.TextLine(
title=_(u"Filter condition"),
description=_(u"Users search additional filtering criteria. "
u"Reference usage: Advanced search instructions"),
required=True)
)
class IBloodSample(model.Schema):
uuid = schema.TextLine(
title=_(u"UUID"),
required=True,
readonly=False,
)
sample_no = schema.TextLine(
title=_(u"Sample number"),
required=True,
)
barcode = schema.TextLine(
title=_(u"Barcode"),
required=False,
)
name = schema.TextLine(
title=_(u"Name"),
required=True,
)
sex = schema.TextLine(
title=_(u"Sex"),
required=True,
)
age = schema.Int(
title=_(u"Age"),
min=0,
max=200,
required=True,
)
inspection_item = schema.TextLine(
title=_(u"Inspection item"),
required=True,
)
inspection_method = schema.TextLine(
title=_(u"Inspection method"),
required=True,
)
submission_hospital = schema.TextLine(
title=_(u"Submission hospital"),
required=False,
)
submission_department = schema.TextLine(
title=_(u"Submission department"),
required=False,
)
submission_doctor = schema.TextLine(
title=_(u"Submission doctor"),
required=False,
)
pathological_diagnosis = schema.TextLine(
title=_(u"Pathological diagnosis"),
required=False,
)
pathological_no = schema.TextLine(
title=_(u"Pathological number"),
required=False,
)
treatment_situation = schema.List(
title=_(u"Treatment situation"),
required=False,
value_type=schema.Choice(
title=_(u"Treatment"),
vocabulary="gene.tumour.vocabulary.treatment_situation",
required=True),
)
received_operator = schema.TextLine(
title=_(u"Received operator"),
required=False,
)
received_phone = schema.TextLine(
title=_(u"Received phone"),
required=False,
)
received_address = schema.TextLine(
title=_(u"Received address"),
required=False,
)
sample_type = schema.TextLine(
title=_(u"Sample type"),
required=True,
)
sampling_time = schema.Datetime(
title=_(u"Sampling time"),
constraint=validate_time,
required=False,
)
received_time = schema.Datetime(
title=_(u"Received time"),
constraint=validate_time,
required=False,
)
sample_size = schema.TextLine(
title=_(u"Sample size "),
required=False,
)
sample_note = schema.TextLine(
title=_(u"Sample note"),
required=False,
)
sample_source = schema.TextLine(
title=_(u"Sample source"),
required=False,
)
tcc_tcp = schema.Float(
title=_(u"TCC/TCP"),
description=_(u"Glass inspection"
u"(Percentage of tumor cells/tumor cells)"),
required=False,
min=0.0,
max=1.00,
)
@invariant
def pre_older_after(obj):
prev = 'sampling_time'
after = 'received_time'
prev_value = getattr(obj, prev, None)
after_value = getattr(obj, after, None)
if after_value is not None:
if (prev_value is not None
and isinstance(prev_value, datetime.datetime)
and isinstance(after_value, datetime.datetime)
and prev_value > after_value):
raise Invalid(
_(u'After steps time must be greater than '
u'or equal to the previous steps time'))