Function that i created to manage some data.

filterData.py

def __condition(o_value,operator,value):
    if operator == '==':
        return (o_value == value)
    elif operator == '!=':
        return (o_value != value)
    elif operator == '<':
        return (o_value < value)
    elif operator == '>':
        return (o_value > value)
    else: 
        return False

def __satisfy(obj,condition):
    field=str(condition['field'])
    operator=str(condition['operator'])
    value=str(condition['value'])
    if obj:
        if __condition(str(obj[field]),operator,value):
            return obj
        else:
            return None
    return None

def filterData(objects, conditions, condition_operator='and'):
    '''
        takes a list and a condition, return a sublist
        condition is list of dic containing:
        - field
        - operator
        - value
    '''
    listret = []
    for obj in objects:
        obj_t_l = []
        for condition in conditions:
            obj_t = __satisfy(obj,condition)
            if condition_operator=='and':
                obj=obj_t
            else:
                if obj_t is not None:
                    obj_t_l.append(obj)
        if condition_operator=='and' and obj:
            listret.append(obj)           
        elif len(obj_t_l) > 0:
            obj=obj_t_l[0]
            listret.append(obj)
    ret={}
    ret['result']=listret
    return ret

JoinObjects.py

def joinObjects(objects, field):
    '''
        takes a list of objects and merge them.
        objects are dicts
        if objects have same keys, values are joined into a list.
        [{'id':1,'tag':'ciao1'},
        {'id':2,'tag':['ciao1',ciao3]},
        {'id':1,'smt':'else2'},
        {'id':2,'tag':'ciao2'}] 
        becomes
        [{'id': 1,'smt': 'else2', 'tag': 'ciao1'}, {'id': 2,'tag': ['ciao2', 'ciao1','ciao3']}]
    '''
    ret = []
    res = {}
    for obj in objects:
#        find the index
        idx = obj[field]
#        find the object
        if idx in res:
            t_obj = res[idx]
        else:
            t_obj = {}
            
        for k,v in obj.iteritems():
#            if key is the field don't do anything
            if k is not field:
                if k in t_obj:
#                    if it's a list then append it, so we avoid list into lists
                    if isinstance(t_obj[k], list):
                        t_obj[k].append(v)
                    else:
                        t_obj[k]=[v]+t_obj[k]
                else:
                    if isinstance(v, list):
                        t_obj[k]=v
                    else:
                        t_obj[k]=[v]
            else:
                t_obj[k]=v  
#            store in the map
        res[idx] = t_obj
    r = []
#    for all the elements in the list (which are dict)
    for k, v in res.iteritems():
        obj={}
#        take all the fields of an element
        for k1,v1 in v.iteritems():
            if isinstance(v1, list):
                if len(v1)==1:
                    obj[k1]=v1[0]
                else:
                    obj[k1]=v1
            else:
                obj[k1]=v1
        r.append(obj)
    return r

MergeData.py

def mergeData(data):
'''
Merge Lists into a single list:
[[1, 2, 3], [5, 6], 7] -> [1, 2, 3, 5, 6, 7]
'''
    ret = []
    for d in data:
        value = d
#        if list then concat element
        if isinstance(value, list):
            ret=ret+value
#        if not append the element
        else:
            ret.append(value)      
    return ret

splitObjects.py

def splitObjects(objects, shared, fields):
    '''
        takes a list of objects and split in two lists.
        shared are the fields shared by both objects
        fields are the fields of the first object.
        remaining fields are for the second object.
        data=[{'id':1,'tag':['ciao1','ciao2'],'smt':"else"},{'id':2,'tag':['ciao1','ciao2','ciao3']}]  
        result=[
                [{'tag': ['ciao1', 'ciao2'], 'id': 1}, 
                 {'tag': ['ciao1', 'ciao2', 'ciao3'], 'id': 2}
                ], 
                [
                 {'smt': 'else', 'id': 1}, 
                 {'id': 2}
                ]
               ]
    '''
    list1=[]
    list2=[]
    for obj in objects:
        item1={}
        item2={}
        for key, value in obj.iteritems():
            if key in shared:
                item1[key]=value
                item2[key]=value
            elif key in fields:
                item1[key]=value
            else:
                item2[key]=value
        list1.append(item1)
        list2.append(item2)
    ret = []
    ret.append(list1)
    ret.append(list2)
    return ret