Update Map zoom_control variable to also allow string to set position (#1884)

* Updated zoom_control variable to handle either True/False or position

* Updated description and added check on valid position values

---------

Co-authored-by: Frederic Berrouet <frederic.berrouet@telecomitalia.it>
Co-authored-by: Frank Anema <33519926+Conengmo@users.noreply.github.com>

Author: 3 people

folium/folium.py

@@ -151,8 +151,9 @@ class Map(JSCSSMixin, MacroElement):
         Forces Leaflet to not use hardware-accelerated CSS 3D
         transforms for positioning (which may cause glitches in some
         rare environments) even if they're supported.
-    zoom_control : bool, default True
-        Display zoom controls on the map.
+    zoom_control : bool or position string, default True
+        Display zoom controls on the map. The default `True` places it in the top left corner.
+        Other options are 'topleft', 'topright', 'bottomleft' or 'bottomright'.
     font_size : int or float or string (default: '1rem')
         The font size to use for Leaflet, can either be a number or a
         string ending in 'rem', 'em', or 'px'.
@@ -214,6 +215,10 @@ class Map(JSCSSMixin, MacroElement):
             L.control.scale().addTo({{ this.get_name() }});
             {%- endif %}
 
+            {%- if this.zoom_control_position %}
+            L.control.zoom( { position: {{ this.zoom_control|tojson }} } ).addTo({{ this.get_name() }});
+            {%- endif %}
+
             {% if this.objects_to_stay_in_front %}
             function objects_in_front() {
                 {%- for obj in this.objects_to_stay_in_front %}
@@ -256,7 +261,7 @@ def __init__(
         no_touch: bool = False,
         disable_3d: bool = False,
         png_enabled: bool = False,
-        zoom_control: bool = True,
+        zoom_control: Union[bool, str] = True,
         font_size: str = "1rem",
         **kwargs: TypeJsonValue,
     ):
@@ -290,10 +295,21 @@ def __init__(
         self.crs = crs
         self.control_scale = control_scale
 
+        # Zoom control position specified ?
+        if isinstance(zoom_control, str):
+            self.zoom_control_position = True
+            if zoom_control not in {"topleft", "topright", "bottomleft", "bottomright"}:
+                raise ValueError(
+                    "Incorrect value for `zoom_control`, choose from 'topleft', 'topright', 'bottomleft' or 'bottomright'."
+                )
+            self.zoom_control = zoom_control
+        else:
+            self.zoom_control_position = False
+
         self.options = parse_options(
             max_bounds=max_bounds_array,
             zoom=zoom_start,
-            zoom_control=zoom_control,
+            zoom_control=False if self.zoom_control_position else zoom_control,
             prefer_canvas=prefer_canvas,
             **kwargs,
         )