Fix Codacy Warnings (#477)

---------

Co-authored-by: Dario Coscia <dariocos99@gmail.com>

pina/collector.py

@@ -1,5 +1,5 @@
 """
-# TODO
+Module for the Collector class.
 """
 
 from .graph import Graph
@@ -7,16 +7,23 @@ from .utils import check_consistency
 
 
 class Collector:
+    """
+    Collector class for collecting data from the problem.
+    """
 
     def __init__(self, problem):
+        """ "
+        Initialize the Collector class, by creating a hook between the collector
+        and the problem and initializing the data collections.
+
+        :param AbstractProblem problem: The problem to collect data from.
+        """
         # creating a hook between collector and problem
         self.problem = problem
 
         # those variables are used for the dataloading
         self._data_collections = {name: {} for name in self.problem.conditions}
-        self.conditions_name = {
-            i: name for i, name in enumerate(self.problem.conditions)
-        }
+        self.conditions_name = dict(enumerate(self.problem.conditions))
 
         # variables used to check that all conditions are sampled
         self._is_conditions_ready = {
@@ -26,26 +33,61 @@ class Collector:
 
     @property
     def full(self):
+        """
+        Return True if all conditions are ready.
+        """
+
         return all(self._is_conditions_ready.values())
 
     @full.setter
     def full(self, value):
+        """
+        Set the full property of the collector. Admit only boolean values.
+
+        :param bool value: The value to set the full property to.
+        """
         check_consistency(value, bool)
         self._full = value
 
     @property
     def data_collections(self):
+        """
+        Return the data collections, created by combining together all condition
+        in the problem.
+
+        :return: The data collections.
+        :rtype: dict
+        """
+
         return self._data_collections
 
     @property
     def problem(self):
+        """
+        Property that return the problem connected to the collector.
+
+        :return: The problem connected to the collector.
+        :rtype: AbstractProblem
+        """
         return self._problem
 
     @problem.setter
     def problem(self, value):
+        """
+        Return the problem connected to the collector.
+
+        return: The problem connected to the collector.
+        rtype: AbstractProblem
+        """
+
         self._problem = value
 
     def store_fixed_data(self):
+        """
+        Store inside data collections the fixed data of the problem. These comes
+        from the conditions that do not require sampling.
+        """
+
         # loop over all conditions
         for condition_name, condition in self.problem.conditions.items():
             # if the condition is not ready and domain is not attribute
@@ -66,7 +108,8 @@ class Collector:
 
     def store_sample_domains(self):
         """
-        # TODO: Add docstring
+        Store inside data collections the sampled data of the problem. These
+        comes from the conditions that require sampling.
         """
         for condition_name in self.problem.conditions:
             condition = self.problem.conditions[condition_name]