如何从字典中打印带有可变数量的键+值的格式化字符串

Question

Is it possible to print variable amount of key+values from a dictionary with str.format()? It would be nice if that would work in python2.

let's say I have a dictionary with some amount of keys+values, and I have to print keys+values of those keys which are stored in a list/tuple.

dict1 = { 'k1':'v1', 'k2':'v2', 'k3':'v3'}
to_print = ('k1', 'k2')
string = ''
for i in dict1:
    if i in to_print:
        string += "{" + i + "} " +  ', '

string = string.format(**dict1)
print(string[:-2])

The above code gives

v1 , v2 

while I would like it to be formatted like this:

[k1] v1 , [k2] v2

UPD:

having challenges with that solution if a dictionaries are inside a list and i need to print key/values from one dictionary in one row, example:

list1  = [ { 'k1':'v1', 'k2':'v2', 'k3':'v3'} , { 'k1':'v4', 'k2':'v5', 'k3':'v6'} ] 
to_print = ('k1', 'k2')
for i in list1:
    for k,v in i.items():
        if k in to_print:
            elements = []
            elements.append(f"[{k}]: {v}")
            print(", ".join(elements))
[k1]: v1
[k2]: v2
[k1]: v4
[k2]: v5

while I need something like this:

[k1]: v1 , [k2]: v2
[k1]: v4 , [k2]: v5

Previously, I addressed that with the grouped function from the SO:

def grouped(iterable, n):
    "s -> (s0,s1,s2,...sn-1), (sn,sn+1,sn+2,...s2n-1), (s2n,s2n+1,s2n+2,...s3n-1), ..."
    return zip(*[iter(iterable)] * n)

any idea to make that better?

ok, figured that out:

elements = []
for i in list1:
    elements = []
    for k,v in i.items():
        if k in to_print:
            elements.append(f"[{k}]: {v}")
    print(", ".join(elements))```

Answer 1

dict1 = { 'k1':'v1', 'k2':'v2', 'k3':'v3'}
to_print = ('k1', 'k2')

elements = []
for key, val in dict1.items():
    if key in to_print:
        elements.append(f"[{key}]: {val}")

print(", ".join(elements))

Or could be done even shorter by using list comprehension:

print(", ".join([f"[{key}]: {val}" for key, val in dict1.items() if key in to_print]))

will yield:

[k1]: v1, [k2]: v2, [k3]: v3