diff --git a/src/humanize/filesize.py b/src/humanize/filesize.py
index 050bed06..6e1f57e0 100644
--- a/src/humanize/filesize.py
+++ b/src/humanize/filesize.py
@@ -60,17 +60,22 @@ def naturalsize(
 
     if abs_bytes == 1 and not gnu:
         return "%d Byte" % bytes_
-    elif abs_bytes < base and not gnu:
+
+    if abs_bytes < base and not gnu:
         return "%d Bytes" % bytes_
-    elif abs_bytes < base and gnu:
+
+    if abs_bytes < base and gnu:
         return "%dB" % bytes_
 
     for i, s in enumerate(suffix):
         unit = base ** (i + 2)
+
         if abs_bytes < unit and not gnu:
             return (format + " %s") % ((base * bytes_ / unit), s)
-        elif abs_bytes < unit and gnu:
+
+        if abs_bytes < unit and gnu:
             return (format + "%s") % ((base * bytes_ / unit), s)
+
     if gnu:
         return (format + "%s") % ((base * bytes_ / unit), s)
     return (format + " %s") % ((base * bytes_ / unit), s)
diff --git a/src/humanize/number.py b/src/humanize/number.py
index 0c71e822..c62a6142 100644
--- a/src/humanize/number.py
+++ b/src/humanize/number.py
@@ -145,8 +145,8 @@ def intcomma(value: NumberOrString, ndigits: int | None = None) -> str:
     new = re.sub(r"^(-?\d+)(\d{3})", rf"\g<1>{sep}\g<2>", orig)
     if orig == new:
         return new
-    else:
-        return intcomma(new)
+
+    return intcomma(new)
 
 
 powers = [10**x for x in (3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 100)]
@@ -213,20 +213,13 @@ def intword(value: NumberOrString, format: str = "%.1f") -> str:
 
     if value < powers[0]:
         return negative_prefix + str(value)
-    for ordinal, power in enumerate(powers[1:], 1):
+
+    for ordinal_, power in enumerate(powers[1:], 1):
         if value < power:
-            chopped = value / float(powers[ordinal - 1])
+            chopped = value / float(powers[ordinal_ - 1])
             if float(format % chopped) == float(10**3):
-                chopped = value / float(powers[ordinal])
-                singular, plural = human_powers[ordinal]
-                return (
-                    negative_prefix
-                    + " ".join(
-                        [format, _ngettext(singular, plural, math.ceil(chopped))]
-                    )
-                ) % chopped
-            else:
-                singular, plural = human_powers[ordinal - 1]
+                chopped = value / float(powers[ordinal_])
+                singular, plural = human_powers[ordinal_]
                 return (
                     negative_prefix
                     + " ".join(
@@ -234,6 +227,12 @@ def intword(value: NumberOrString, format: str = "%.1f") -> str:
                     )
                 ) % chopped
 
+            singular, plural = human_powers[ordinal_ - 1]
+            return (
+                negative_prefix
+                + " ".join([format, _ngettext(singular, plural, math.ceil(chopped))])
+            ) % chopped
+
     return negative_prefix + str(value)
 
 
@@ -334,10 +333,11 @@ def fractional(value: NumberOrString) -> str:
         # this means that an integer was passed in
         # (or variants of that integer like 1.0000)
         return f"{whole_number:.0f}"
-    elif not whole_number:
+
+    if not whole_number:
         return f"{numerator:.0f}/{denominator:.0f}"
-    else:
-        return f"{whole_number:.0f} {numerator:.0f}/{denominator:.0f}"
+
+    return f"{whole_number:.0f} {numerator:.0f}/{denominator:.0f}"
 
 
 def scientific(value: NumberOrString, precision: int = 2) -> str:
@@ -464,13 +464,14 @@ def clamp(
 
     if isinstance(format, str):
         return token + format.format(value)
-    elif callable(format):
+
+    if callable(format):
         return token + format(value)
-    else:
-        raise ValueError(
-            "Invalid format. Must be either a valid formatting string, or a function "
-            "that accepts value and returns a string."
-        )
+
+    raise ValueError(
+        "Invalid format. Must be either a valid formatting string, or a function "
+        "that accepts value and returns a string."
+    )
 
 
 def metric(value: float, unit: str = "", precision: int = 3) -> str:
@@ -515,15 +516,15 @@ def metric(value: float, unit: str = "", precision: int = 3) -> str:
 
     value /= 10 ** (exponent // 3 * 3)
     if exponent >= 3:
-        ordinal = "kMGTPEZY"[exponent // 3 - 1]
+        ordinal_ = "kMGTPEZY"[exponent // 3 - 1]
     elif exponent < 0:
-        ordinal = "mμnpfazy"[(-exponent - 1) // 3]
+        ordinal_ = "mμnpfazy"[(-exponent - 1) // 3]
     else:
-        ordinal = ""
+        ordinal_ = ""
     value_ = format(value, ".%if" % (precision - (exponent % 3) - 1))
-    if not (unit or ordinal) or unit in ("°", "′", "″"):
+    if not (unit or ordinal_) or unit in ("°", "′", "″"):
         space = ""
     else:
         space = " "
 
-    return f"{value_}{space}{ordinal}{unit}"
+    return f"{value_}{space}{ordinal_}{unit}"
diff --git a/src/humanize/time.py b/src/humanize/time.py
index 1d1222f4..c28d5aa3 100644
--- a/src/humanize/time.py
+++ b/src/humanize/time.py
@@ -151,7 +151,8 @@ def naturaldelta(
                     _ngettext("%d microsecond", "%d microseconds", delta.microseconds)
                     % delta.microseconds
                 )
-            elif min_unit == Unit.MILLISECONDS or (
+
+            if min_unit == Unit.MILLISECONDS or (
                 min_unit == Unit.MICROSECONDS and 1000 <= delta.microseconds < 1_000_000
             ):
                 milliseconds = delta.microseconds / 1000
@@ -160,47 +161,59 @@ def naturaldelta(
                     % milliseconds
                 )
             return _("a moment")
-        elif seconds == 1:
+
+        if seconds == 1:
             return _("a second")
-        elif seconds < 60:
+
+        if seconds < 60:
             return _ngettext("%d second", "%d seconds", seconds) % seconds
-        elif 60 <= seconds < 120:
+
+        if 60 <= seconds < 120:
             return _("a minute")
-        elif 120 <= seconds < 3600:
+
+        if 120 <= seconds < 3600:
             minutes = seconds // 60
             return _ngettext("%d minute", "%d minutes", minutes) % minutes
-        elif 3600 <= seconds < 3600 * 2:
+
+        if 3600 <= seconds < 3600 * 2:
             return _("an hour")
-        elif 3600 < seconds:
+
+        if 3600 < seconds:
             hours = seconds // 3600
             return _ngettext("%d hour", "%d hours", hours) % hours
+
     elif years == 0:
         if days == 1:
             return _("a day")
+
         if not use_months:
             return _ngettext("%d day", "%d days", days) % days
-        else:
-            if not num_months:
-                return _ngettext("%d day", "%d days", days) % days
-            elif num_months == 1:
-                return _("a month")
-            else:
-                return _ngettext("%d month", "%d months", num_months) % num_months
+
+        if not num_months:
+            return _ngettext("%d day", "%d days", days) % days
+
+        if num_months == 1:
+            return _("a month")
+
+        return _ngettext("%d month", "%d months", num_months) % num_months
+
     elif years == 1:
         if not num_months and not days:
             return _("a year")
-        elif not num_months:
+
+        if not num_months:
             return _ngettext("1 year, %d day", "1 year, %d days", days) % days
-        elif use_months:
+
+        if use_months:
             if num_months == 1:
                 return _("1 year, 1 month")
-            else:
-                return (
-                    _ngettext("1 year, %d month", "1 year, %d months", num_months)
-                    % num_months
-                )
-        else:
-            return _ngettext("1 year, %d day", "1 year, %d days", days) % days
+
+            return (
+                _ngettext("1 year, %d month", "1 year, %d months", num_months)
+                % num_months
+            )
+
+        return _ngettext("1 year, %d day", "1 year, %d days", days) % days
 
     return _ngettext("%d year", "%d years", years).replace("%d", "%s") % intcomma(years)
 
@@ -265,12 +278,16 @@ def naturalday(value: dt.date | dt.datetime, format: str = "%b %d") -> str:
         # Date arguments out of range
         return str(value)
     delta = value - dt.date.today()
+
     if delta.days == 0:
         return _("today")
-    elif delta.days == 1:
+
+    if delta.days == 1:
         return _("tomorrow")
-    elif delta.days == -1:
+
+    if delta.days == -1:
         return _("yesterday")
+
     return value.strftime(format)
 
 
@@ -323,10 +340,11 @@ def _quotient_and_remainder(
     """
     if unit == minimum_unit:
         return value / divisor, 0
-    elif unit in suppress:
+
+    if unit in suppress:
         return 0, value
-    else:
-        return divmod(value, divisor)
+
+    return divmod(value, divisor)
 
 
 def _carry(
@@ -361,10 +379,11 @@ def _carry(
     """
     if unit == min_unit:
         return value1 + value2 / ratio, 0
-    elif unit in suppress:
+
+    if unit in suppress:
         return 0, value2 + value1 * ratio
-    else:
-        return value1, value2
+
+    return value1, value2
 
 
 def _suitable_minimum_unit(min_unit: Unit, suppress: typing.Iterable[Unit]) -> Unit:
@@ -405,16 +424,16 @@ def _suppress_lower_units(min_unit: Unit, suppress: typing.Iterable[Unit]) -> se
     ['MICROSECONDS', 'MILLISECONDS', 'DAYS']
     """
     suppress = set(suppress)
-    for u in Unit:
-        if u == min_unit:
+    for unit in Unit:
+        if unit == min_unit:
             break
-        suppress.add(u)
+        suppress.add(unit)
 
     return suppress
 
 
 def precisedelta(
-    value: dt.timedelta | int,
+    value: dt.timedelta | int | None,
     minimum_unit: str = "seconds",
     suppress: typing.Iterable[str] = (),
     format: str = "%0.2f",
diff --git a/tests/test_i18n.py b/tests/test_i18n.py
index 87ce3bb9..4824d05b 100644
--- a/tests/test_i18n.py
+++ b/tests/test_i18n.py
@@ -156,7 +156,7 @@ def test_default_locale_path_null__file__() -> None:
 def test_default_locale_path_undefined__file__() -> None:
     i18n = importlib.import_module("humanize.i18n")
     del i18n.__file__
-    i18n._get_default_locale_path() is None
+    assert i18n._get_default_locale_path() is None
 
 
 class TestActivate:
diff --git a/tests/test_time.py b/tests/test_time.py
index 924df985..d37fb6a3 100644
--- a/tests/test_time.py
+++ b/tests/test_time.py
@@ -629,6 +629,8 @@ def test_precisedelta_suppress_units(
 
 
 def test_precisedelta_bogus_call() -> None:
+    assert humanize.precisedelta(None) == "None"
+
     with pytest.raises(ValueError):
         humanize.precisedelta(1, minimum_unit="years", suppress=["years"])
 
@@ -640,7 +642,6 @@ def test_time_unit() -> None:
     years, minutes = time.Unit["YEARS"], time.Unit["MINUTES"]
     assert minutes < years
     assert years > minutes
-    assert minutes == minutes
 
     with pytest.raises(TypeError):
         _ = years < "foo"