arcpy - Getting value from Metadata in Python Script for attribute?

I am working on a python script to create some feature classes from dbf tables. As part of the script I would like to pull two values (FGDC "publication date" and ArcGIS Spatial Reference ArcGIS Coordiante System "Projection") from the metadata of a linear referencing feature class and write them to a field in the feature class. I've looked at some of the modules that parse .xml files, but the linear referencing feature class doesn't have a standalone .xml. Below is the part of the script where i'd like to pull and calculate the values.

#Pull COORDSYS and MAPVERSION from RCI Metadata

    #Calculate Values for Coordsys, Mapsource, MapVersion, publish date, CAR xfer date, coord xfer date
    today = datetime.date.today()

    pub_date = today.strftime("%m/%d/%y")
    arcpy.CalculateField_management(input,"COORDSYS",XXX,"PYTHON_9.3")
    arcpy.CalculateField_management(input,"MAPSOURCE",mapsource_ON,"PYTHON_9.3")
    arcpy.CalculateField_management(input,"MAPVERSION",XXX,"PYTHON_9.3")
    arcpy.CalculateField_management(input,"DTPUBLISHE",pub_date,"PYTHON_9.3")
    arcpy.CalculateField_management(input,"DTCARXTRCT",pulldate,"PYTHON_9.3")
    arcpy.CalculateField_management(input,"DTCOORDXTR",pub_date,"PYTHON_9.3")

Answer

Here is the code that finally did the trick. This is the same method proposed by Helene above. Any comments on how to improve this are welcome.

    #Create XML from RCI Basemap Metadata

    translator = "C:\Program Files (x86)\ArcGIS\Desktop10.2\Metadata\Translator\ARCGIS2FGDC.xml"
    arcpy.ExportMetadata_conversion(roads,translator,arcpy.env.workspace+"\\"+"roads_Export.xml")

    #Get MAPVERSION from RCI Basemap
    from xml.etree.ElementTree import ElementTree
    from xml.etree.ElementTree import Element, SubElement

    xmlfile = arcpy.env.workspace+"\\"+"roads_Export.xml"

    tree = ElementTree()

    tree.parse(xmlfile)

    spot = tree.find("idinfo/citation/citeinfo/pubdate")
    pub_date = spot.text

    year = pub_date[0:4]
    month = pub_date[4:6]
    month_num = int(month)

    if 0 < month_num < 3:

        version = year+"Q1"
    elif 3 < month_num < 6:
        version = year+"Q2"
    elif 6 < month_num < 9:
        version = year+"Q3"
    elif 9 < month_num < 12:
        version = year+"Q4"

    #Calculate Values for Coordsys, Mapsource, MapVersion, publish date, CAR xfer date, coord xfer date


    arcpy.CalculateField_management(input,"MAPVERSION",'"{0}"'.format(version),"PYTHON")