code: def sigmoid(v, x):
      """This is the EC50 sigmoid function
  
      v is a vector of parameters:
          v[0] = minimum allowed value
          v[1] = maximum allowed value
          v[2] = ec50
          v[3] = Hill coefficient
      """
      p_min, p_max, ec50, hill = v
      return p_min + ((p_max - p_min) / (1 + (x / ec50) ** hill))
  
imports: import functools
  import os
  import numpy
  import scipy.optimize
  from cellprofiler_core.constants.measurement import EXPERIMENT
  from cellprofiler_core.constants.measurement import IMAGE
  from cellprofiler_core.constants.measurement import NEIGHBORS
  from cellprofiler_core.constants.module import IO_FOLDER_CHOICE_HELP_TEXT, IO_WITH_METADATA_HELP_TEXT
  from cellprofiler_core.measurement import Measurements
  from cellprofiler_core.module import Module
  from cellprofiler_core.preferences import ABSOLUTE_FOLDER_NAME
  from cellprofiler_core.preferences import DEFAULT_INPUT_FOLDER_NAME
  from cellprofiler_core.preferences import DEFAULT_INPUT_SUBFOLDER_NAME
  from cellprofiler_core.preferences import DEFAULT_OUTPUT_FOLDER_NAME
  from cellprofiler_core.preferences import DEFAULT_OUTPUT_SUBFOLDER_NAME
  from cellprofiler_core.setting import Binary
  from cellprofiler_core.setting import Divider
  from cellprofiler_core.setting import Measurement
  from cellprofiler_core.setting import SettingsGroup
  from cellprofiler_core.setting import ValidationError
  from cellprofiler_core.setting.do_something import DoSomething
  from cellprofiler_core.setting.do_something import RemoveSettingButton
  from cellprofiler_core.setting.text import Directory
  from cellprofiler_core.setting.text import Text
label_desc: Use image node_id 6 for calling a global function with example usage: sigmoid(v, x) and returns: unknown