diff --git a/banana/cli.py b/banana/cli.py
index d29aa97..a6fe0e1 100644
--- a/banana/cli.py
+++ b/banana/cli.py
@@ -1,8 +1,9 @@
 """Console script for banana."""
 import argparse
-from . import bananalib as banana
 import sys
 
+from . import bananalib as banana
+
 
 def ananas2dec():
     parser = argparse.ArgumentParser(description="Convert ananas string to dec")
@@ -23,12 +24,16 @@ def avocado2dec():
 def banana2dec():
     parser = argparse.ArgumentParser(description="Convert banana string to dec")
     parser.add_argument("banana", help="String to be converted")
-    parser.add_argument("--dictionary", help="Set dictionary", type=list, nargs='+')
-    parser.add_argument("--dictstart", help="Set starting dictionary", type=int, default=0)
-    parser.add_argument("--shiftend", help="Set shift for ending dictionary", type=int, default=0)
+    parser.add_argument("--dictionary", help="Set dictionary", type=list, nargs="+")
+    parser.add_argument(
+        "--dictstart", help="Set starting dictionary", type=int, default=0
+    )
+    parser.add_argument(
+        "--shiftend", help="Set shift for ending dictionary", type=int, default=0
+    )
     args = parser.parse_args()
 
-    print(banana.banana2dec(args.banana, args.dictstart, args.shiftend, args.dictionary))
+    print(banana.banana2dec(args.banana))
 
 
 def ribes2dec():
@@ -41,13 +46,21 @@ def ribes2dec():
 
 def bananarandom():
     parser = argparse.ArgumentParser(description="Generate random banana")
-    parser.add_argument("--dictionary", help="Set dictionary", type=list, nargs='+')
-    parser.add_argument("--dictstart", help="Set starting dictionary", type=int, default=0)
-    parser.add_argument("--shiftend", help="Set shift for ending dictionary", type=int, default=0)
+    parser.add_argument("--dictionary", help="Set dictionary", type=list, nargs="+")
+    parser.add_argument(
+        "--dictstart", help="Set starting dictionary", type=int, default=0
+    )
+    parser.add_argument(
+        "--shiftend", help="Set shift for ending dictionary", type=int, default=0
+    )
     parser.add_argument("--minlength", help="Set minimum length", type=int, default=6)
     args = parser.parse_args()
 
-    print(banana.bananarandom(args.dictstart, args.shiftend, args.minlength, args.dictionary))
+    print(
+        banana.bananarandom(
+            args.dictstart, args.shiftend, args.minlength, args.dictionary
+        )
+    )
 
 
 def dec2ananas():
@@ -71,13 +84,21 @@ def dec2avocado():
 def dec2banana():
     parser = argparse.ArgumentParser(description="Convert dec number to banana")
     parser.add_argument("num", help="Number to be converted", type=int)
-    parser.add_argument("--dictionary", help="Set dictionary", type=list, nargs='+')
-    parser.add_argument("--dictstart", help="Set starting dictionary", type=int, default=0)
-    parser.add_argument("--shiftend", help="Set shift for ending dictionary", type=int, default=0)
+    parser.add_argument("--dictionary", help="Set dictionary", type=list, nargs="+")
+    parser.add_argument(
+        "--dictstart", help="Set starting dictionary", type=int, default=0
+    )
+    parser.add_argument(
+        "--shiftend", help="Set shift for ending dictionary", type=int, default=0
+    )
     parser.add_argument("--minlength", help="Set minimum length", type=int, default=0)
     args = parser.parse_args()
 
-    print(banana.dec2banana(args.num, args.dictstart, args.shiftend, args.minlength, args.dictionary))
+    print(
+        banana.dec2banana(
+            args.num, args.dictstart, args.shiftend, args.minlength, args.dictionary
+        )
+    )
 
 
 def dec2ribes():
@@ -92,9 +113,13 @@ def dec2ribes():
 def isbanana():
     parser = argparse.ArgumentParser(description="Checks if string is banana")
     parser.add_argument("banana", help="String to be checked")
-    parser.add_argument("--dictionary", help="Set dictionary", type=list, nargs='+')
-    parser.add_argument("--dictstart", help="Set starting dictionary", type=int, default=0)
-    parser.add_argument("--shiftend", help="Set shift for ending dictionary", type=int, default=0)
+    parser.add_argument("--dictionary", help="Set dictionary", type=list, nargs="+")
+    parser.add_argument(
+        "--dictstart", help="Set starting dictionary", type=int, default=0
+    )
+    parser.add_argument(
+        "--shiftend", help="Set shift for ending dictionary", type=int, default=0
+    )
     args = parser.parse_args()
 
     print(banana.isbanana(args.banana, args.dictstart, args.shiftend, args.dictionary))
@@ -107,4 +132,3 @@ def main():
 if __name__ == "__main__":
     # pragma: no cover
     main()
-
diff --git a/tests/test_banana.py b/tests/test_banana.py
index 2314791..30c70f2 100644
--- a/tests/test_banana.py
+++ b/tests/test_banana.py
@@ -6,16 +6,13 @@ import pytest
 from banana import (avocado2dec, banana2dec, dec2avocado, dec2banana,
                     dec2ribes, ribes2dec)
 
-banana_conversions = {
-    "ba": 0,
-    "baba": 0,
-    "be": 1,
-    "beba": 70,
-    "zu": 69,
-    "bezu": 139,
-    "nana": 2485,
-    "banana": 2485,
-}
+banana_conversions = {"be": 1, "beba": 70, "zu": 69, "bezu": 139, "nana": 2485}
+
+
+@pytest.fixture(params=banana_conversions.items())
+def banana_known(request):
+    yield request.param
+
 
 avocado_conversions = {
     "a": 0,
@@ -39,6 +36,12 @@ avocado_conversions = {
     "ega": 90,
 }
 
+
+@pytest.fixture(params=avocado_conversions.items())
+def avocado_known(request):
+    yield request.param
+
+
 ribes_conversions = {"b": 0, "c": 1, "z": 13, "beb": 14, "bec": 15}
 
 
@@ -47,24 +50,21 @@ def ribes_known(request):
     yield request.param
 
 
-def test_banana_to_dec_known():
-    for word, value in banana_conversions.items():
-        assert banana2dec(word) == value
+def test_banana_to_dec_known(banana_known):
+    word, value = banana_known
+    assert banana2dec(word) == value
 
 
-def test_banana2dec_prefix_ba():
+def test_dec_to_banana_known(banana_known):
+    word, value = banana_known
+    assert dec2banana(value) == word
+
+
+def test_banana2dec_prefix_ba(banana_known):
     """un ba all'inizio non cambia nulla!"""
-    for word in banana_conversions:
-        value = banana2dec(word)
-        for prefix in ("ba", "baba", "bababa"):
-            assert banana2dec(prefix + word) == value
-
-
-def test_dec_to_banana_known():
-    for word, value in banana_conversions.items():
-        if word.startswith("ba"):
-            continue
-        assert dec2banana(value) == word
+    word, value = banana_known
+    for prefix in ("ba", "baba", "bababa"):
+        assert banana2dec(prefix + word) == value
 
 
 def test_ribes_to_dec_known(ribes_known):
@@ -72,19 +72,19 @@ def test_ribes_to_dec_known(ribes_known):
     assert ribes2dec(word) == value
 
 
-def test_dec_to_ribes_known():
-    for word, value in ribes_conversions.items():
-        assert dec2ribes(value) == word
+def test_dec_to_ribes_known(ribes_known):
+    word, value = ribes_known
+    assert dec2ribes(value) == word
 
 
-def test_avocado_to_dec_known():
-    for word, value in avocado_conversions.items():
-        assert avocado2dec(word) == value
+def test_avocado_to_dec_known(avocado_known):
+    word, value = avocado_known
+    assert avocado2dec(word) == value
 
 
-def test_dec_to_avocado_known():
-    for word, value in avocado_conversions.items():
-        assert dec2avocado(value) == word
+def test_dec_to_avocado_known(avocado_known):
+    word, value = avocado_known
+    assert dec2avocado(value) == word
 
 
 def test_answer_to_life_the_universe_and_everything():