Command : Description | Arity | Left | Right | Pythonish Representation
( ): NOP | NA | NA | NA
(!): Length of right argument | 1 | NA | Iterable | length(right)
   : Factorial of right argument | 1 | NA | Number | factorial(right)
("): Start/close string | 0 | NA | NA | NA
(#): Comment | NA | NA | NA | NA
($): Sort the right argument | 1 | NA | Iterable | sorted(right)
(%): Modulo of left and right | 2 | Number | Number | left % right
   : Formats a string | 2 | String | String | left.format(right)
(&): Logical and | 2 | Any | Any | left && right
('): Delimit a variable name
((): Start a list | NA | NA | NA | NA
()): End a list | NA | NA | NA | NA
(*): Multiply left and right | 2 | Number | Number | left * right
   : Repeat left by right times | 2 | Iterable | Number | left * right
   : Product of iterables | 2 | Iterable | Iterable | list(itertools.product(left, right))
(+): Add left and right | 2 | Number | Number | left + right
   : Add left and right | 2 | String | String | left + right
   : Append right to left | 2 | List | Any | left.append(right)
(,): Separate list items | 0 | NA | NA | NA
(-): Subtraction | 2 | Number | Number | left - right
(.): Special constants | 0 | NA | NA | NA
(/): Divison | 2 | Number | Number | left / right
(0): Number
(1): Number
(2): Number
(3): Number
(4): Number
(5): Number
(6): Number
(7): Number
(8): Number
(9): Number
(:): Double the input | 1 | NA | Any | [right, right]
(;): Decrement | 1 | NA | Any | right - 1
(<): Less than | 2 | Any | Any | left < right
(=): Equality | 2 | Any | Any | left == right
(>): Greater than | 2 | Any | Any | left > right
(?): Input, eval'd | 0 | NA | NA | keta_eval(input())
(@): String ender
(A): Absolute value | 1 | NA | Number | abs(right)
(B): Binary to base 10 | 1 | NA | Number | int(2, right)
(C): Ceiling | 1 | NA | Number | math.ceil(right)
(D): Double | 1 | NA | Number | right * 2
(E): Eval | 1 | NA | String | keta_eval(right)
(F): Factorise | 1 | NA | Number | find_factors(right)
(G): Generate range from 0 to right (inclusive) | 1 | NA | Number | range(0, right + 1)
(H): Halve | 1 | NA | Number | right / 2
(I): If statement | 2* | Expression | Block | if(expression, blocks)
(J): Join x with y | 2 | Iterable | String | right.join(left)
(K): Constant library | 1 | NA | Character | constants[right]
(L): List range | 2 | Number | Number | range(left, right + 1)
(M): Map function to iterable | 2 | Iterable | Block | map(right, left)
(N): Negate | 1 | NA | Number | right * -1
(O): One-dimensionify a list (flatten) | 1 | NA | Iterable | [item for sublist in l for item in sublist]
(P): Permutation | 2 | Iterable | Number | itertools.permutations(left, right)
(Q): Quit/terminate program | 0 | NA | NA | exit()
(R): Reduce by block | 2 | Iterable | Block | functools.reduce(right, left)
(S): Square | 2 | Iterable | Number | textwrap.wrap(left, right)
(T): Top of stack | 1 | NA | Iterable | right[0]
(U): Uniquify | 1 | NA | Iterable | unique(right)
(V): Variable set | 2 | String | Any | left = right
(W): While loop | 2 | Expression | Block | While(left, right)
(X): Exclude/remove items | 2 | Iterable | Any | list(filter((right).__ne__, left))
(Y): Loop variable
(Z): Zip | 2 | Iterable | Iterable | zip(left, right)
([): Start a block
(\): Escape the next character
(]): End a block
(^): Exponentiate
(_): Truthify
(`): String ender
(a): all | 1 | NA | Iterable | all(right)
(b): binary representation | 1 | NA | Any | bin(right)
(c): contains | 2 | Iterable | Any | right in left
(d): divmod | 2 | Number | Number | divmod(left, right)
(e): exec | 1 | NA | String | keta_exec(right)
(f): filter | 2 | Iterable | Block | keta_filter(left, right)
(g): generate exclusive range | 1 | NA | Number | range(0, right)
(h): hack/stride | 2 | Iterable | Iterable(Number, Number) | left[right[0]:right[1]]
(i): loop variable 
(j): loop variable
(k): loop variable
(l): Lookup/index | 2 | Iterable | Any | left.index(right)
(m): maximum | 2 | Any | Any | max(left, right)
(n): newline | 0 | NA | NA | NA
(o): or | 2 | Any | Any | left or right
(p): print | 1 | NA | Any | print(right)
(q): quoted | 1 | NA | Any | str(right)
(r): repeat | 2 | Number | Block | repeat(right, left)
(s): shape | 2 | Iterable | Number | shape(left, right)
(t): tail of stack | 1 | NA | Iterable | right[-1]
(u): uniquified sorted | 1 | NA | Iterable | sorted(uniquified(right))
(v): variable get | 1 | NA | String | variable_name
(w): wrap | 2 | Iterable | Number | left[::right]
(x): index | 2 | Iterable | Number | left[right]
(y): loop variable
(z): z(s)leep | 1 | NA | Number | time.sleep(right)
({): Start a block
(|): Separate items
(}): End a block
(~): Random number